The aim of this chapter will include; an attempt to establish the nature of the controversy between direct and indirect realism right from the period of John Locke who had established the foundations for the debate. The rationalists had come to lay a foundation of our knowledge on supposedly certain and indubitable foundations in reasoning, Locke too, in his empiricism began to occupy a position referred to as ‘indirect realism’ due to his argument that objects of experience cannot be directly perceived. But before then, an attempt shall be made to account for the nature of the argument of the realists as against the position of the anti-realists’ divide in epistemology. Going back to the period of the British empiricists with our main point of focus on Locke, and Berkeley. Having mentioned earlier that there is a divide between direct and indirect realists, the difference boiling largely out of how one perceives what one perceives, it will be considerate to account therefore for the nature of the debate between the both of them and the attempts of the direct realists to escape the two arguments (arguments from illusion and hallucination) rendered against it by the indirect realists.
1.1 Contemporary Realist Arguments
The problem of perception is one that has been in the mind of several philosophies ever since the period before Socrates, where we see philosophers like Democritus and Leucippus who claimed that physical objects are really composed of tiny indivisible particles referred to as atoms. The problem which is popularly referred to as ‘the problem of perception’ has been given a new formulation. Epistemologists concerned with the problem of perception seek to enquire how we come to perceive the contents of the external world. Before going any further, I shall try to define what perception itself entails.
Perception is the process by which we, through any of our five senses- eyes, ears, tongue, nose and skin, gain knowledge of the external world. It is due to this kind of definition that one is bound to think that it is something pertaining to empiricism alone. It is indeed a valid assertion, since it seems to lay emphasis upon the senses and the kind of connection they have with the world in the bid to acquire knowledge. We should note that in the light of the above definition, there is a distinction between what exists in the world, and what we perceive as existing. According to this conception, there are several theories. These theories of perception try to answer the question of what and how we can know through sense experience and they include: realism and anti-realism.
1.2 Realism vs. Anti-Realism
The argument of the realists is entailed in their conception that objects of the world exist independent of the mind. For the realists, every physical thing we perceive would exist even if we were not around to perceive them, it could therefore be said that for the realists, perception is mind-independent. That is there does not have to be a mind before the existence of a physical object could be ascertained. This implies that the relation between perceiver and the perceived is not of a dependent form. For the anti-realists however, perception is mind-dependent. This means that everything that exists only exists because there is a mind perceiving them. It may look like they are saying that perception is a temporal thing because the implication will be that what is not being at the moment perceived by some mind cannot be claimed to exist until otherwise perceived.
We should note that the above outline of the divide between realists and anti-realists is that of an old tradition as we shall come to see in the work of John Locke. It is not the case that their doctrines have changed, but we shall attempt to account for possible modifications in the various positions. Our next contention thus, shall be to try to articulate the positions of contemporary realists in the problem of perception.
As already outlined above, realism is that epistemological position in the problem of perception that holds that what we perceive in the external world is independent of our perceptive faculties. For the realists, perception is mind independent so that the external world is a permanent fixate that our senses only come to apprehend whenever we attempt to perceive. Realists claim that physical objects exist as things that are independent of our minds and of our perceptions of them. A realist believes that there is a world (the “material” world) that exists independently of whether or not any conscious mind experiences it. A realist believes that if all the minds (mental beings) stopped existing tomorrow, there would still be a world out there, just one that no one was conscious of.
An example of a realist is John Locke, whose philosophy of perception helped define the lines of indirect realism today. Another is David Hume who is credited with the saying below:
…this very table, which we see white, and which we feel hard, is believed to exist, independent of our perception, and to be something external to our minds, which perceives it.
1.3 Direct Vs. Indirect Realism
Our main aim in this section is to discuss contemporary views on realism, but this will not be possible if the several views are not themselves divided into two other schools, the direct/naïve realists, and the indirect/sophisticated realists.
As much as realism is the school that holds that whatever it is we perceive, its existence is not dependent on the mind, the position of the direct/naïve realists is that objects of perception are directly apprehended, that we have a direct access to the physical objects of the external world. Direct realists claim that we perceive the physical objects themselves. When we perceive the world, it certainly appears to us as it is exactly we directly perceive physical objects that exist independently of our minds. Direct realism claims that the immediate object of perception is the physical object itself. We don’t perceive it in virtue of perceiving something else that ‘mediates’ between our minds and the physical object.
The indirect realists however are also referred to as representative realists. An example of an indirect realist will be John Locke who claims that what we perceive are not the objects but an idea of the object in the world and since an idea is not a physical but a mental thing then it means that what we perceive according to indirect realism is just an intermediary between object and perceiver. This means that they advocate for an intermediary between objects of perception and the perceiver.
The contemporary argument of the representative realists is informed in their critic of the arguments against the direct realists. This is using the arguments from illusion and the argument from hallucination. We shall talk better on this later in this chapter. Bertrand Russell is an example of an indirect realist, another example is G.E Moore.
1.4 The Empiricism of John Locke
With the aim of the continental rationalists being built on the idea of innate ideas, which says that every mind is born with ideas, for them whatever it is we claim to know must have been built upon the certain ideas that was in our minds at birth. This seemed to make sense, since their aim was (Descartes for example) to establish a certain foundation from which all knowledge would emerge, and they thought that the mind would be that certain foundation in contrast to experience, thus the doctrine of innatism.
So, in being an empiricist, the aim of John Locke was to unsettle the previous philosophy before him, rationalism and their doctrine of innatism, Descartes wanted to provide a solid, indubitable foundation for knowledge, however Locke viewed rationalism as resting upon unquestioned assumptions, like the assumption that the mind is born with ideas at birth, and the further assumption that clarity of concepts can give accurate knowledge of reality.
It seemed to him, like he’d successfully showed the inadequacy of the rationalist foundations, so Locke proceeded to assert that the mind was born at birth blank, empty, this is where his concept of tabula rasa originates. Unlike the innatists, whatever it is we eventually come to know is not a function of the mind, but that of experience, from the senses. This eventually exposed the modest and humble beginnings of Locke’s epistemology. This is because unlike Descartes who wanted a deductively certain foundation, Locke agreed that the senses are not certain source of knowledge (as we shall come to see). This eventually rendered him a modest empiricist.
Since Locke had asserted that unlike Descartes, the foundation of his own empiricism is not built on the concept of a blank slate, then it seemed empirical for him to proceed how it is that our sense from the outside world help to imprint ideas in the mind.
Let us then suppose the mind to be, as we say, white paper, void of all characters, without any ideas: —How comes it to be furnished? Whence comes it by that vast store which the busy and boundless fancy of man has painted on it with an almost endless variety? Whence has it all the materials of reason and knowledge? To this I answer, in one word, from EXPERIENCE. In that all our knowledge is founded; and from that it ultimately derives itself.
So, for Locke, experience is the source from which all of our knowledge arises and not the mind. He described the processes according to which the sense derived ideas from the external world as the process of sensation. In sensation the senses gets ideas from the physical objects out there, and through reflection the mind is able to impose its characteristic functions of composition and abstraction on the idea gotten from the external world.
…by reflection then, in the following part of this discourse, I would be understood to mean, that notice which the mind takes of its own operations, and the manner of them, by reason whereof there come to be ideas of these operations in the understanding.
This is the origin of simple and complex ideas in Lockean epistemology; the eyes for instance perceive a simple object of sensation like a man and a horse. But the mind, being able to compose and sometimes abstract the simple ideas gotten from sight is able to form a further idea of a centaur which although has no existence in reality. This process of compounding ideas together is referred to as ‘reflection’, the combination of both processes is what gives us the knowledge that we end up claiming to have, for one without the other is not sufficient considering that even Locke claimed that in sensation, the mind is passive, but in reflection, active.
1.4.1 Lockean Indirect Realism
In perceiving the objects of the external world, Locke claims that what we actually perceive is not the object itself, rather we only perceive qualities. This will imply that those qualities must in some way or the other possess a sense of reality, a reality they owe to being a part of a material object. This may seem like what follows, but in our distinction between the types of qualities there are, we shall come to see the idea take some concrete shape. He defines qualities as ‘the ability of an object to cause ideas in our mind’. This is to take care of the Cartesian question of whether or not the mind has an accurate representation of the contents of the external world. It is in his distinction and explanation of the types of qualities that we have as we shall come to see that the position of Locke as an indirect realist is explicitly seen.
Since it is the case that we do not always have an accurate representation of the objects out there, and since Locke had established that what we perceive are not the objects themselves but only an idea of them[i], then it seemed normal for him to posit that in the object themselves are some qualities, these he called primary and the other are outside of the object, this he called secondary qualities. Primary qualities are the qualities that are inherent in the objects of perception, they are ‘primary’ to the objects and once they are abstracted from the object, then it can never remain the same. They are objective, universal and include: solidity, extension, figure, mobility, bulk, weight, texture - “…are utterly inseparable from body…” The secondary qualities however, are not of the same nature, they do not reside in the object of perception and are not ‘primary’ to it. They are only conceived in the minds of the perceiver, they are subjective and are the representations that the mind perceives in objects. They include color, taste, smell, sound, [felt] temperature and are caused in us by primary qualities. They are why we can claim to have perceptual errors since they are not identical to the object, but are only comprehended by each perceiver. Unlike the primary qualities therefore, they are not universal. They are the reasons Locke is considered an indirect realist today. While the ideas that primary qualities produce in us resemble those qualities in the objects that caused us to have those ideas, the ideas that secondary qualities produce in us do not resemble those qualities in the objects that caused us to have those ideas.
Whatever realities we may by mistake ascribe to them, colors, smell sound and taste (secondary qualities) are nothing but qualities produced in us by the primary or real qualities of objects – sensation, which in no way resembles the qualities which exists in the object
This explains how it is that there is a distinction between both primary and secondary qualities as well as the process of perception and the object of perception. If Locke will go by saying that primary qualities are the real qualities of objects in being resident in the object itself, then we perceive much more than these qualities for existence cannot be denied of the secondary qualities either, this renders us with evidence for no other conclusion than that since they differ, they must report separate realities, thus we do not have direct access to the objects of perception. This is how it is that Locke ends up being an indirect realist.
The consequence of this is that the world does not appear to us the way it really is, since secondary qualities are really distinct from the primary qualities which are seen to be in the object itself, and unlike the primary qualities, our ideas of secondary qualities do not resemble the object itself, thus they are only really appearances and are distinct from the object. The modern version of this notion is entailed in the indirect realist’s idea of sense data for which Locke is rightly credited for having established foundations for.
1.5 Representationalist Theory of Perception
Having asserted the intricacies of Lockean indirect realism and how it led us to the conclusion of his being a representationalist in his claim that , we shall now examine the idea behind the representationalist theory itself and what it entails in length. The grounds for the reprsentationalist theory of perception could be found in the arguments that the indirect realists raised against the direct or naïve realists. I however shall desist from rendering an explanation to it in the current section for the next section will be committed to it.
Representationalists say that we perceive ‘indirectly’; what we perceive ‘directly’ is a ‘representation’, a mental image, that exists in our minds but which represents the physical object. The physical object is perceived ‘via’ this representation. The representation is an ‘appearance’; philosophers have called it a ‘sense-datum’. So for the representationalist, they argue that though we do perceive the world, there is a difference between how the world looks like, and how we perceive it. What occurs to our consciousness is different from what ought to occur for it is a mere representation of reality. This might sound like a contradiction, but it is the argument of the indirect realists.
Several philosophers have likened the representationalist distinction between what exists and what we perceive as being similar to that in which Aristotle made between appearance (what appears to exist) and reality (what exists). Since in the representationalist vocabulary, the physical objects differ from the sense datum, perception is therefore incomplete until there is sense-datum. We shall attempt outlining some of the features or characteristics of the sense-datum.
‘Sense data’ was originated by Bertrand Russell, but was first put into use by G.E Moore, they are seen to be the direct objects of perception in the indirect realist’s vocabulary. Sense datum is that which is given directly in perception by the senses, sometimes referred to as the data of immediate awareness. Some would refer to it as the immediate mental effect of brain or neural activities resulting from stimulation of sense organs by the external object. One should however not mistake them for the cause of perception, so that sense data theory does not become a causal theory. It should not be taken as causal especially since we can have instances perceptual relativity, illusion and hallucination which suggests that even if it will be causal; it ought to be an adequate cause. We shall now proceed to outline the features of sense datum.
- Sense-data are ‘private’, they are subjective in character. They are the particular data from the senses in a particular consciousness. By contrast, physical objects are ‘public’. One and the same table can be experienced by different people.[ii]
- Sense-data only exist while they are being experienced. An experience must be
experienced by someone to exist at all. A physical object, such as a table, can exist when no one experiences it. Thus they are temporal.
- Sense-data are exactly as they seem. As we said above, they are ‘appearances’. There is no further reality to an appearance than how it appears. Physical objects can appear differently from how they really are (e.g. the stick in water). They have a reality which is not defined by appearance.
It seems however, that the indirect realists, in Humean terms were ‘multiplying entities unnecessarily’ as it does seem like we would have to create a new world for these set of entities called ‘sense data’ since it has been shown that they do not reside in the object, neither do they reside in the perceiver. So the indirect realist faces the problem of being able to account for a comprehensive nature for these new set of entities without contradiction.
1.6 Direct Realism vs. Indirect Realism Theory of Perception
The distinction between the tenets of direct realism and the indirect has so far been clearly defined. We shall make an attempt to account for the argument of the indirect realists, this shall be included in the aim of the present section, besides trying to assert an enquiry into the nature of the divide.
While the argument of the direct realist hinges on the notion of our ability to directly and immediately perceive the objects of perception, the arguments of the indirect realists has been an attempt to render direct realism which of course holds contrary views to them incoherent and thus unacceptable as an adequate theory of perception. The indirect realist uses mainly two ‘severe’ critiques against direct realism, which establishes their own positions as indirect realists. These arguments include: the argument from illusion and the argument from hallucination.
1.6.1 The Argument from Illusion
In illusions, we perceive objects, but not as they really are. The most common examples of this kind of a perceptual error is the example of the bent stick in water which under normal conditions would not be bent. This kind of argument would seem to undermine direct realism, as it would then require an extra explanation for this kind of perceptual error.
Indirect Realist’s Argument: The indirect realist however is able to conveniently accommodate the notion of a perceptual error given the concept of ‘sense data’. The argument is that since all we can really perceive are sense-datum, then whatever we seem to perceive is not the object but a sense-datum of it, thus it is not the stick that is bent in water, but only our sense data of it makes it appear so.
The direct realist would however in an attempt to disprove the indirect realist claim that the argument from illusion might unsettle his own tenets, but it is not sufficient to establish the grounds for indirect realism. If sense data attempt to represent the world to us, and if they are the only objects of perception, then we ought not to be able to have illusions, because illusions are cases of what is not appearing as it is, but since sense data is all we perceive, then how do we know for sure that it renders an inaccurate representation of the world beyond it? In fact, since it is the nature of sense data to be variant and subjective, then how do we really claim to have uniform knowledge of the external world?
1.6.2 The Argument from Hallucination
If in cases of illusion, we ‘misperceive’, then in hallucinations, we see something, but nothing which exists, for instance a mirage.
Indirect Realist’s Argument: For the indirect realist thus, whenever we have instances of perceiving when there really is no external object behind the perception, then what we perceive cannot be the object since it does not even exist, but sense datum. Like the previous one, the direct realist seems pushed into a corner for the lack of an explanation to this obvious deficiency in his theory, so once again the indirect realist attempts to establish the foundations of his notions of sense data by claiming that what we perceive that does not exist is nothing but sense data for there really is no physical object behind it.
The direct realist would again attempt a reply, for them; as much as a version of the argument against the indirect realist in the argument from illusion can be rendered here as well, one is pushed to consider the idea behind an hallucination: instances of experiencing what does not in fact exist. But if sense data is a representation of the external object, and since it is possible to perceive sense data when in fact there is nothing is represents, then how could we ascribe adequate credentials of representation to it? Just as much as to claim not to have an accurate account of perception is to know what exists beyond what appears to us (the sense data).
We see how Locke is justifiably referred to as an indirect realist, due to his distinction between the different kinds of qualities. The contemporary arguments for indirect realism and how they introduced the concept of ‘sense data’ is also looked into. We also try to establish the boundaries between the arguments of the direct and the indirect realists with the nature of the controversy in mind and the possible counter arguments that a direct realist would attempt to use to rescue their argument.
[i] This is another explanation of his representationalist position since what the indirect realist claim is that it is not the object we perceive, but only mediation, a representation of it.
[ii] We should here remember Locke’s description of the secondary qualities as being subjective and the primary as being objective and universal.
 Anthony Kenny: A New History of Western Philosophy: Volume 1: Ancient Philosophy. Clarendon Press: Oxford. Oxford University Press Inc., New York, 2004. p. 50
 Lacewing, Micheal: Representative Realism.p.1
 ibid: p. 1
 ibid: p. 1
 Hume, David: An Enquiry Concerning Human Understanding (1748/1772) 12.8
 Lacewing, Micheal: Representative Realism.p.1
 Group, T. a. (2014, 07 06). Philosophy for AS. Frances and Taylor Group. p.3
 Ibid: 3
 Anthony Kenny: A New History of Western Philosophy: Volume 1: Ancient Philosophy. Clarendon Press: Oxford. Oxford University Press Inc., New York, 2004. p. 53
 Locke, John. An Essay Concerning Human Understanding. In The Empiricists. Garden City, New York: Anchor Books, 1974, pg. 1.
 ibid, pg.2.
 Locke, John. An Essay Concerning Human Understanding. Book II, Chapter I: Of Ideas In General, And Their Original.
 Locke, John. An Essay Concerning Human Understanding. Book II. Of Ideas in General, And Their Original. Book II
 Anthony Kenny: A New History of Western Philosophy: Volume 1: Ancient Philosophy. Clarendon Press: Oxford. Oxford University Press Inc., New York, 2004. p. 53
 Ibid: 53
 Locke, John. An Essay Concerning Human Understanding. Book II. Chapter VIII: Some Further Considerations Concerning Our Simple Ideas of Sensation. Primary Qualities of Bodies. Secondary Qualities of Bodies. Book VIII)
 Alfred Weber, The Philosophy of John Locke, pg. 5
 Lacewing, Micheal: Representative Realism, pg. 2.
 Encyclopedia of Philosophy 7, Sense Data, pg. 478
 Lacewing, Micheal: Representative Realism, p.6
 Ibid: p. 6
We have in the previous chapter attempted to account for the arguments of John Locke and how it is that we arrive at our conclusion of his being an indirect realist from his distinction between primary and secondary qualities. The aim of the present chapter shall be in three-folds: a critical assessment of Locke’s representative position, a look into the subjective idealism of Bishop George Berkeley, influenced by Locke to propound a thesis that disagrees with common sense, and finally a critique of the school of indirect realism as a whole.
2.1 A Critical Appraisal of Locke’s Indirect Realism
At the outset, before Locke laid his theory of empiricism, the very first thing he did was to attempt to debunk the concept of innatism upon which rationalism was built, so that he may erect his own empirical theory upon it. We should note that the claim that the concept of innatism that Locke seemed to radically object against is one that bases its foundations on the metaphysical concept of God. Some contrary version of innatism that does not have itself built on a metaphysical Being who ‘puts’ ideas in our minds at birth is however discernible in the works of Noam Chomsky.
The contention is that Locke’s critic would only be valid against innatism of the Cartesian frame of mind, those that seek to ascribe for the ideas we have at birth to God as the source. This may not be a critic against Locke’s position, but it is sure an instance of a point for the rationalists, and a stream of thought worth pursuing. Most attempts at criticizing Locke’s philosophy come from two major aspects against his thought. It is either such critic seeks to undermine his contention that primary and secondary qualities are sufficient to establish the contents of experience, or it is the case that they seek to establish that Locke’s conclusion in his concept of substratum or substance as a concept that exists but yet is that which we ‘know not what’ is unfounded, and could lead to skepticism. It is an adoption of both frames of mind however that the philosophy of Bishop Berkeley adopted in his attempt to undermine the basics of Lockean epistemology.
To begin with, we shall first talk about the concept of matter upon which Locke lay the existence of primary qualities. In an attempt to achieve comprehensiveness, and having propounded that there were primary and secondary qualities, one existing in the object therefore of necessary significance to its retaining its identity. The other only produced in the mind of the perceiver by the primary qualities and so subjective to each perceiver, he found it an essential conclusion to propound in turn some concept in which these ideas of primary qualities (if not the secondary) subsist.
For him, the existence of such concept is necessary due to the fact that the mentioned qualities must have at least a coherent existence in the external world. Such a concept in which they would exist cannot be an idea since it is supposed to serve as a kind of pillar to primary and secondary qualities. The point of Locke’s argument thus necessitated the existence of the material substratum so that it may hold both primary and secondary qualities. Thus, following the dictates of his representationalist empiricism, Locke argued that the qualities we perceive in the objects of the external world cannot hang in the air and are in need of a support. He maintained that there must be a substratum or support to which these qualities are attached.
Locke however claimed that such material thing is that which ‘we know not what’ because it is not possible to infer the existence of something outside of the primary qualities that our senses can perceive. Matter is conceived as an inert, senseless, and unknown substance. This is why Locke had referred to it as “I know, not what”. Matter neither acts, nor perceives, nor is perceived and it is mostly made up of negatives. The only positive supposition about matter is that it is a “support to qualities”.
If this is the kind of reading that we acquire from Locke, of an inert matter that cannot act but is only perceivable due to its possessing the character of upholding primary and secondary qualities, then this as asserted in the previous chapter is what makes Locke an indirect realist, so that most if not all the arguments tenable against indirect realism may be tenable against Locke too. We shall however take account of some of the objections against Locke’s epistemology.
According to William T. Jones he contends that the indirect realist’s division of our ideas has a fundamental flaw that is contrary to experience, Locke laid his notion of “idea” as being constituents of the mind, he divided these features of the mind into two, the simple and the complex. While simple ideas are the constituents derived originally from experience, the complex ones are nothing but combinations of simple ideas. For instance the simple ideas of a “fish” and a woman compound to birth the complex idea of a “mermaid”, something not obtainable in experience. The understanding from here is that when we perceive a mental idea of an “apple” for instance, what should occur to the perceiver’s mind should be the simple ideas of red, sweet, and round to be compounded into the complex idea of an apple. Experience shows otherwise, for the reverse is the case. It is until the complex idea of “apple” has been perceived before we are able to arrive at more simple ideas that are supposed to compound it. It is thus the case that Locke’s division of ideas into the simple and complex and the features he ascribed to them will lead to conclusions that are contrary to experience.
To consider another critique however, this critique seeks to show how it is that Locke’s position can lead to skepticism about the existence of material substances. Berkeley substituted Locke’s position with his idealism so he moving totally away from the realm of matter. Granted that Locke claims that primary qualities are contained in the object of perception, it is supposed to be the case that our understanding of the nature of the substratum in which these qualities subsist so that we can infer that for the quality to exist, there must be something in which it subsist. Locke’s position however will not allow us arrive at that conclusion for he seems to think that qualities have to exist before we can proceed to the existence of the matter behind them. And since he ended up being an indirect realist as explained in the previous chapter, then we are left with no other option but having to infer the material substance behind said qualities. If Locke claims that all we perceive are the ideas of primary and secondary qualities, then the material substance to which these qualities belong are beyond our experience and so can only be inferred. But experience is once again contrary to this implication, for there are instances in which we do not even notice some of the qualities that a material substance possesses, but notice it in its entirety, as a combination of the qualities it possesses.
The last of the critics that shall be rendered against Locke shall be one that seeks to question the causal connection between physical objects and the ideas of primary and secondary qualities that they cause. To know that primary qualities exist in the external object is to know for sure that such physical object exists. For the explanation of the origin of the qualities is that they exist in the physical object out there. For Locke however to retract and disclaim having any relevant knowledge of the object is a curious point to take. Since existence of the qualities depend upon it, there is no reason to deny existence to it. If the connection is really a causal one, then to a large extent there ought to be an adequate account of the cause and the effect proceeding from such cause.
Having laid several standard critics against Locke, we shall proceed to the next British empiricist after Locke, Bishop George Berkeley and his subjective idealism.
2.2 Bishop George Berkeley’s Doctrine of Subjective Immaterialism
Berkeley was an Irishman of theological inclinations, for which reason he was said to have been a Bishop who contributed to the philosophy of his era in a way that according to several commentators today contradict with the dictates of common sense. This is largely due to the position Berkeley held in his empiricism, a position he derived from that of John Locke. It is believed that it is in an attempt to push Locke’s ideas to an extreme in an attempt at criticism that helped Berkeley arrive at his own thesis on the nature of perception especially as seen in his New Theory of Vision (1709), An Essay Concerning Principles of Human Knowledge (1710) and The Three Dialogues between Hylas and Philonaus (1713).
The point that Berkeley was a Bishop played much role in the formulation of his thread of empiricism. Previous thoughts had created problems that could lead to confusions about questions of the world being based upon the guidance of God the Ultimate Ruler of the Universe. Berkeley thought that there were three views current in his day that threatened the Christian faith: the skeptical belief that nothing could be known for certain, the materialism that comes from Hobbes which seemed to imply atheism, and the belief, among those that believed in God, that God had no continuous involvement with the universe. So it could be surmised that he wanted to argue mainly against atheism as well as skepticism.
As earlier mentioned, Berkeley turned out being a subjective idealist, and it was due to his critique of Locke that helped him arrive at the conclusion that he did. It is this aspect of his thought as an idealist that we are concentrating upon.
2.2.1 Berkeley’s Critique against Lockean Distinction between Primary and Secondary Qualities
His arguments against Locke’s position as in indirect realism stems mainly from two aspects of the latter’s philosophy: his claim about the nature of the existence of matter or substratum and his distinction between primary and secondary qualities. In fact, most of his arguments were raised against Locke’s doctrine of material substratum. He also contends that another thesis that supports the idea of material substance is the distinction between primary and secondary qualities.
The attempt at the critique could be seen in his The Three Dialogues between Hylas and Philonous, where we see Hylas means “wood” in Greek, implying “matter” and the word ”Philonous” a combination of “philo” which means “love” and “nous” which means, “mind”. Philonous is thus a lover of the mind, who asserts that every reality is mental. It is from the conversation between these two that we are able to discern Berekeley’s position on the nature of the existence of matter.
Locke had divided the various kinds of qualities, and for him qualities are “the ability of an object to cause ideas in our mind” we have into two, one he claimed was primary and was supposed to be “…utterly inseparable from (the) body…” and included solidity, extension, figure, mobility, bulk, weight, and texture, it is their character to exist even without the perception of some being of them since they are in the material object of perception and are thus said to be objective. The secondary qualities however differ from the primary on the grounds that they are the representations that the mind perceives in objects, they include color, taste, smell, sound, [felt] temperature and are caused in us by primary qualities, thus they are an topic of the mind and are subjective. This distinction ran Locke into a wall because it helped give Berkeley the right to accuse him of having contradicted himself.
It is however until we note the Lockean comment that even primary qualities are ideas in the mind. Locke recognizes this and affirms that they are in the object and also in the mind since they are qualities, and are in their nature mental. Let us consider that the ideas of extension and solidity for instance which are stated to be primary qualities and hence are understood as the original qualities that belong to the material substance. These are also gained through the sense of touch and hence are sensations in the mind. We cannot separate the idea of extension from the idea of color and other so-called secondary qualities. When we perceive anything extended we perceive it as colored and having other secondary qualities also. Going by his own distinction between the two, this would ordinarily amount to a contradiction, which Berkeley subscribes to. To claim that they exist both in the object and the mind might amount not just to a contradiction in Berkeley, but also help achieve a unity of the ideas of both primary and secondary qualities since both exist in the mind, thus for Berkeley, all we have are qualities and so there is no distinction between primary and secondary qualities.
Berkeley believed that the weakest point in this whole philosophical edifice was the very notion of matter, conceived of as some sort of mind-independent stuff adequately characterizable in terms of the so-called primary qualities alone.
If Locke is going to ascribe to the material substance that supposedly upholds the qualities features of being unknown, then it will imply that every quality of an object can be reduced to a sensible quality or to a sensation, and these are supposed to be conscious in the sense of being perceivable which will be an ability they are endowed with and immaterial. Berkeley argues that there is nothing beyond sensations and hence every reality is mental. To put it in another way, let us consider that Berkeley seeks to hold that the idea of a material substance that could possibly exist behind the qualities independent of the mind may pose the threat of atheism and irreligion. Because it implies an independent material substance inert, incapable of acting. But when we experience, we do get some form of data from the external world. These datum cannot arise from the matter of Locke, so it must have an alternate source, this could only be qualities. These qualities are not inert in nature. So an adequate condition for perception is that that which we perceive must be active as much as the mind is. And in being active cannot be material, it therefore has to be some immaterial thing. Since we cannot deny that we perceive, then whatever it is we perceive cannot but be an idea, all of our experience is composed of active non-physical events, they are the real contents of not just experience, but the external world. And in the above fashion, we establish Berkeley’s immaterialism.
Admittedly, the argument as outlined above justifying Berkeley’s immaterialism is held to be contrary to common-sense. However, we cannot deny the conclusion he had arrived at, perhaps impracticable, but the only conclusion to which he could push Locke’s position. We shall now proceed to explain Berkeley’s subjectivism.
According to Berkeley, a mind is a mind because it contains ideas, this is because what defines its nature as a mind is because of the ideas it contains, or the fact that it contains them at all. As much as ideas do not have an independent existence outside of the mind. Thus, for an idea to be, it must be the contents of the experience of some mind. Then for existence to be ascribed to a particular thing, it has to first exist in some mind. So Berkeley’s most famous saying that esse est percipii meaning ‘to be is to be perceived’ –by a mind, can be observed from this stream of thought. This would mean that existence is subjective to some mind. This is apparent in his famous analogy during the conversation between Hylas and Philonous in the Three Dialogues between Hylas and Philonous. We are invited to imagine an instance of an object existing unperceived such as a tree in a forest for instance. For Hylas, it will be impossible think about an object that is not the subject of the mind of some perceiver. Because
…as I was thinking of a tree in a solitary place, where no one was present to see it, methought that was to conceive a tree as existing unperceived or unthought of, not considering that I myself conceived it all the while.
To think of the tree is to have it is the subject of the perception of whatever mind is doing the thinking.
Since existence is mind-dependent for Berkeley, it will be impossible to have an instance of an existing but unperceived idea. The characteristics of the mind too include that it is not objective but subjective. This is from Cartesian as well as Lockean thoughts. And since Berkeley’s argument about how he ended up an idealist has been established, then it will mean the contents of our mind dependent perceptions are nothing but ideas, hence his subjective idealism.
In an effort at being comprehensive however, Berkeley says that perhaps our perception might be mind-dependent such that what exists only really does as much as it is the subject of the perception of a mind. He postulated an infinite mind from which all ideas project, this necessitated that God exist thus because God is seen to be infinite so will His mind be, and if that is the case, then the mind of God is the infinite mind, while that of man is finite. So, in instances of my leaving my room, that I am not in the room and therefore not perceiving the room does not mean that the room will stop existing, it will exist as much as it is the object of perception of the mind of God.
The next thing to do now is to attempt a critical assessment of Berkeley.
2.3 Critical Assessment of Berkeley’s Argument
“…few idealists after Berkeley argued for idealism. Instead, they argue from idealism.”
- David Stove, Idealism: A Victorian Horror-Story (Part Two)
2.3.1 The Problem of Objectivity
The critique was rendered by Bruce W. Hauptli in his Selected Criticisms of Berkeley for British Empiricism. As much as the critic seeks to show how the problem of objectivity would exist for Berkeley and anyone who subscribes to his theory and the derived conclusion, we shall attempt to add a new twist to Hauptli’s original critique.
“If I perceive a table, it exists. If Fred perceives a table, it exists. What ensures that we see the same table? Given that one has only one’s own sensation to go on, why assume that these are shared by others i.e. that there is a common world?”
The understanding derivable from this question is that of the claim that Berkeley’s position wrongly assumes that different perceivers of a particular object perceive the same thing. But since we do not have the same minds, then on what grounds could such an assumption as this be articulated?
Granted that the mind and ideas are the only things existing in Berkeley’s epistemology. To perceive something therefore will imply that the object of perception is an idea and therefore a constituent of the mind. It has to be of a subjective character. If that is the case, then it will mean that no two perceivers can perceive the same thing, since they do not have the same medium of perception. My subjective experience is unique as much as it is totally inaccessible from some other person’s, it is therefore closed. The implication will be that since two people observing the same ‘idea’ are only perceiving just that, how does one account for the difference in the nature of their perceptions? One reply is to say that we go by the primary quality of extension (that an object is identical to itself as long as it occupies the portion of space it does and none other), or perhaps are we to go by saying that they do not differ but are similar?
If we are to adopt the first kind of reply of the primary quality of extension and so imply a difference, then it will mean that the objects of perception have to occupy some portion of space, before we can only assign to them notions of difference on those grounds. But we do not want to go by that because even Berkeley would not, for the reason that in talking about occupying space, then we speak already of not an idea now, but a material substance existence for which Berkeley had initially denied. To the other reply therefore, that they are similar will imply some notion of objectivity, for it will mean that although proceeding from differing minds, the ideas in these minds are similar. Now several things can be from here implied, one will be that to claim that they are similar is to say that they must have been to some extent compared against each other, and if that is the case then it will contradict their initial nature in being subjective.
For human beings such as ourselves to exist in the same society, it presupposes that there is to some extent a universal underlying character of experience to which each person is a member of and thus would be able to relate to, and with. To deny this point is to deny the fundamental character of human beings where they are projected as social animals. But Berkeley’s position will never allow the existence of this fundamental universals and so would need to posit for his theory an account of how our ideas being subjective, shuts one off from every other’s experiences and yet we obviously exist in the same societies.
We should however note that Berkeley might render a reply in the guise of claiming that it is in the nature of the subjective feature of the mind to differ for the simple fact that it is subjective. But we should not forget that all of the ideas that is constituted in the mind of each perceiver proceeds from just one source: the infinite mind. As much as these ideas proceed from the mind of God, then that the claim that there is no universal source from which our ideas emerge will be rendered devoid of some of its potency. The mind of God unites all the others in the sense of being the origin of the contents of each mind and being the mind to which each and every other mind partakes.
2.3.2 The Avoidance of Universals
The foundations of this present argument can be seen in Hillary Putnam’s After Empiricism, and it involved an analysis of Berkeley’s notion of idea, it is worthy of note that this argument can also be rendered against the later empiricist and skeptic David Hume but since Hume is not currently in our purview, we shall only extort how the argument is relevant against Berkeley.
For Berkeley, there cannot be a ‘general idea’ or an ‘abstract idea’ of the color ‘green’, to ascribe to an idea ‘green’ whether it is a color patch as existing in my mind or a token of the word ‘green’ when such an idea is used for the whole class of green sense-data in the mind , what really happens is that we have in one way or the other compared this particular token with some other tokens in the mind for which we have accepted are ‘green’, and we have in essence claimed that it is similar to them or they are similar to one another. However, to think of a relation of similarity is to assume that there exists universals, because for there to be a comparison between two things, it implies that we think there is a high chance that they are the same, to think so is to assume that they have something in common. All the worst for Berkeley if our comparison comes out successful, where we are able to establish that these ideas are really similar and therefore there must exist some kind of ocean from which all things green are a part of, and a nature of it which they possess, a notion that Berkeley never accommodated.
Much like in the first argument, the reply of Berkeley to this second critic will be that as long as there is an infinite mind that perceives even in the absence of the finite mind, then there can be a universal source from which all ideas of color emerge, and because this provision is available, then that each perceiver perceives a similar color green is an effect of being visited with the same idea by the infinite mind.
2.3.3 The Argument from Perceptual Errors
An adequate assessment of the argument of Berkeley shows an inadequacy of a different kind now, one that the indirect realists showed was the inadequacy ascribed to direct realism, why it was proven to be faulty and thus necessitating an alternate theory to account for the nature of perception. It is a perceptual fact that there are hallucinations and illusions, these are perceptual errors where perceiver seems to perceive an object having specific features in experience when in actual fact it does not, it either does not exist at all in the case of an hallucination or does not exist as possessing the features experience shows it possessing.
For any comprehensive theory of perception, there has to be an account of notions of this kind, so that it is an adequate theory in being able to accommodate the shortcomings that come with subscribing to such as an empiricist’s leniency towards direct and naïve realism. Direct realism claims that the immediate object of perception is the physical object itself. We don’t perceive it in virtue of perceiving something else that ‘mediates’ between our minds and the object, thus the argument from illusion became valid against them since illusion entails misperceiving an object as having qualities it does not in fact have. When indirect realism came onto the scene however, we are invited to consider an alternative theory where there are mental data called sense data between perceiver and perceived, an account of illusions and hallucinations thus will include mention of such private sense data as the explanation for the perceptual errors.
In the Berkely-ian system however, there is no account of an explanation for illusions or hallucinations, all he wanted to account for was the relationship between the mind that does the perceiving and the idea that is the object of perception. This renders his system inadequate on the grounds that he does not take account of perceptual errors that cannot be denied as one of the many flaws of the school of empiricism.
We have seen the nature of the critics against Locke’s indirect realism and how they attempt to undermine his position. The classical critic regardless is found in Berkeley who based the foundations of his anti-common sense subjective idealism on the extremities discernible from Locke’s position in asserting that there is no distinction between primary and secondary qualities, because both can be in the mind and are thus mental, so that all we have left are ideas since Locke had not strictly delineated his conception of the substratum or matter.
We have also seen how Berkeley’s position is on the main refused due to the conclusions of his argumentation, letting himself be guided by the tenets of his theology, he laid all evidence and origin of ideas on the metaphysical concept of God, so that he became even more vulnerable than his idealism allowed.
 Dr. Sreekumar Nellickappilly, IIT Madras. Aspects of Western Philosophy. New Delhi, 2005. Document. p. 3
 Ibid: 3
 Ibid p. 5
 W.T. Jones, Hobbes to Hume: A History of Western Philosophy (second edition) (N.Y. Harcourt Brace, 1969), pp. 243-244
 Lacewing, Micheal. Indirect Realism. London: Routledge Taylor and Francis Group, 2005. 9
 Ibid: 12
 Dr. Sreekumar Nellickappilly, IIT Madras. Aspects of Western Philosophy. New Delhi, 2005. Document. p. 2
 Ibid: 2
 Anthony Kenny: A New History of Western Philosophy: Volume 1: Ancient Philosophy. Clarendon Press: Oxford. Oxford University Press Inc., New York, 2004. p. 53
 Ibid: 53
 Ibid: 57
 Dr. Sreekumar Nellickappilly, IIT Madras. Aspects of Western Philosophy. New Delhi, 2005. Document. p. 6
 Lowe, E.J. Lowe Philosophical Guidebook to Locke On Human Understanding. New York: Francis and Taylor Group, 1995. pp. 53
 Benneth, Jonathan. Bishop George Berkeley :Three Dialogues Between Hylas and Philonous. London: Oxford University Press, 2004. Dialogue 3; pp. 42
Bruce W. Hauptli. Selected Criticisms of Berkeley for British Empiricism. pp. 2
 Ibid: 2
 Hilary Putnam. After Empiricism, Realism With A Human Face (Cambridge: Harvard U.P., 1990), pp. 43-53
 Lacewing, Micheal: Representative Realism. p. 3
In contrast to direct realism, the indirect or representationalist holds an opposing position, for them, the objects of perception are not mind-independent physical objects. In light of this, the representationalist holds two main theses: first, that what is perceived directly or immediately in sensory experience is not some “external” physical or material object, but rather things that are mental or subjective in character—sense-data, according to the most standard versions of the view. Second that the only available reasons deriving from perception for thinking that perceptual beliefs about the physical world are true depend on inference from facts.
The current chapter is an attempt to consider some of the critiques rendered against representative realism and the implications that can be derived from there. An attempt will also be taken to synthesize the positions of Locke and Berkeley on the argument from the nature of primary and secondary qualities and Locke’s substratum. Subsequently, the arguments of Hume with special emphasis on the nature of causation in Locke is taken account of.
3.1 Arguments against the Representationalist Theory of Perception
That the indirect realists have from the objections recognized against the arguments of the direct realists delineated an alternate theory of perception for themselves is not sufficient justification for their position, we shall on this ground, recognize some of the arguments against indirect realism.
3.1.1 Sense Data and Reference
The first question we must ask is this: what is a mental representation? To answer this we must first consider an inherent fact about human beings: we are intentional agents. That is, our mental states—beliefs, imaginations, desires, thoughts perceptions, etc.—refer to or are about things. Also, we can say that a mental state is intentional if there is some object to which it is directed. So, for example, if I have a ‘desire to go to the mall’ it will be an intentional mental state with an object that it refers to, viz. the mall. But it is also something else. It is a propositional attitude; I have a mental posture towards the content of my intentional state. Thus, if X desires that P, X is said to have a propositional attitude towards P. My attitude towards the object is a ‘desiring-relation’ that I go to that object i.e. the mall.
From the above, we understand that our subjective mental feature in sense data is not a complete account of our perception until it has something, some object to which it refers. However, since the character of our mental experience is such that what we directly perceive is sense datum, it is difficult to admit into our scheme of understanding some notion of mental features having some character to which they refer. From the Cartesian distinction between mind and body, we are told that the mind in being res cogitans is unextended unlike the body. This means that it does not occupy space or time. If we are to accept this Cartesian description as valid, the question that arises therefore is whether it is a valid assertion to claim that such mental character as our sense data has something to which it refers.
On the same line of thought, if it is the case that our mental states have some kind of intentionality in having something to which they refer, and as well possess some notion of existence because we express propositional attitudes about them, then is it not the case that what we refer our proposition to is not the physical object to which we wish to refer, but the mental picture that appears in our mind? It is curious whether Descartes had this contention in mind when he laid the foundation for the Cartesian dualism that persists till today. Regardless, it remains a curious turn of events to refer to mental features the way we would to material substances.
3.1.2 The Argument from Causation
Granted that the representationalist in promoting his version of perception has made a distinction between physical objects in the outside world, and the mental characters that appears to us in experience. Since they are only obvious to the mind of the perceiver we say that they are mind-dependent. If the nature of perceptual experience is constituted by the subject’s acquaintance with mind-dependent direct objects distinct from mind-independent physical objects, then how is such experience supposed to constitute a source of knowledge about the presence and nature of any such physical objects themselves? The representationalist might have as well claimed that what exists out there is the mental character to which experience restricts us, behind which they claim the existence of a physical world to which no access regardless is granted. This will lead us to a very idealist conclusion as we see in British empiricist Bishop George Berkeley who in an attempt to push to logical conclusions the argument of John Locke, claimed non-existence to the physical object behind mental perception of mental features like sense data.
The potency of the criticism is realized once we note that the claim of the direct realists who, because of their assertion that physical objects are the direct objects of perception, can end up being a causal theory of perception. This is because, they will be saying that our perception is caused. The same level of criticism can be rendered against the representationalist only a less acceptable version, since they will in essence be claiming that there is a relationship of causation between perceiver and perceived. The only premise is that the cause of our perception is not a physical object but a mental feature.
3.1.3 Illusion and Hallucination Revisited
In the previous chapter, we had established to an extent how it is the case that the arguments from illusion and hallucination as rendered against the direct realists sometimes, in fact most times helps inform the foundational construct upon which representationalism stands. To avoid taking the long journey down the lines of reiteration, the argument goes something like this:
- In a hallucination, we perceive something having some property F.
2. When we perceive something having some property F, then there is something that has this property.
3. We don’t perceive a physical object at all.
4. Therefore, what we perceive must be mental – sense-data.
5. Hallucinations can be experiences that are ‘subjectively indistinguishable’ from real perceptions.
6. Therefore, we see the same thing, namely sense-data, in both hallucinations and real perception.
7. Therefore, in all cases, we see sense-data, and not physical objects, immediately.
8. Therefore, direct realism is false.
It is ironical that this argument, as its viciousness would go is one supposed to be relevant against the direct realist, it could however be as vicious and perhaps even more once it is turned around and rendered against the representationalist.
Granted that the representationalist claims that what we perceive in cases of perception is not the physical object itself, but sense data which is described to be mental. If this is to be held as a valid assertion, then in cases of illusion and hallucination, it proves nothing. That the mental character perceived is nothing like the physical object behind it shows that we know what the physical object looks like. For the perceiver to claim to know that he has an illusion or a hallucination, he must to some extent know of the nature of the external object behind the sense data he supposedly perceives in illusions and know that they do not exist in hallucinations. Knowing that the physical object reports a different account of experience from the sense data is at least evidence of its existence, that the representationalist would stubbornly decide to hold on to that which emits from the object therefore amounts to self-deceit, for then not only can we perceive the mental feature, but there is a physical feature behind this subjective state that causes the mental and reports a different reality.
3.1.4 The Representationalist as a Solipsist
The last objection that will be rendered against the representationalist is that their position can lead to solipsism. Solipsism is the doctrine that only we possess minds, and in some other variant, some solipsists hold that maybe other beings have minds, we cannot know for sure that they think at all, or if they do that they think the way we do.
The character of our mental experience is subjective, this is one of the other features that we inherit from the famous Cartesian distinction. If the representationalist would be claiming that sense data is the object of direct perception, then they would be claiming that what we perceive is evident to only us, so that others will not perceive what we do and the nature of the objective fact behind the subjective experience is ruined.
To the variant of representationalist that claims that we do not perceive physical objects directly, it could be argued that such an assertion is curious, for it will lead to a revival of the Berkeley-ian doctrine of “to be is to be perceived” so that what exists can only be said to exist because there is a mind that perceives it. If this will hold, then it disqualifies the representationalist as an empiricist since the nature of sense experience is not subjective like the strict subjectivity we get from the mind but to an extent objective. And in being an objective fact out there renders the representationalist on another ground an idealist and also a solipsist since sense data is only obvious to our perceptual framework the way they are and to none others.
3.2 A Synthesis of Locke’s and Berkeley’s Positions
Much like philosophy in antiquity, where we see the efforts of the post-Eleatic philosophers to deny Eleatic monism. And so rendering their own postulations in the shadows of the foremost Eleatic who had in his ontology claimed that space could not exist because it enabled “what is” to become “what is-not”. They went ahead in succession to postulate first, a theory that allowed motion without space as in Empedocles, and then one that allowed both motion and space as in Atomism, according to Leucippus and Democritus. So it obtains in the relationship between the foremost of the British empiricists, John Locke and Bishop Berkeley.
The epistemological groundwork of both theories is the fact that they are both empiricists. This enables us to make some valid assertions as to the nature of Locke’s theory in the light of that of Berkeley. Their being both empiricists of course implies that they both subscribe to the version of ideas according to which the mind at birth is a blank slate, in contrast to what a rationalist such as Descartes may claim in asserting the innatists’ position.
The synthesis between Locke and Berkeley shall be recognized on several grounds, and these include:
3.2.1 On the Distinction between Primary and Secondary Qualities
Granted that Berkeley’s critic of Locke was informed pathway in his claim that there are no distinctions between primary and secondary qualities. Partly because even Locke had claimed that they both exist in the mind of the perceiver even if he will deny all manners of coherent existence to the substratum behind said qualities, but more because Berkeley due to his eventual position as an idealist cannot claim existence for primary qualities - there is no substratum in which they would subsist, there is no material object to hold them together and which should serve as their support. Also in consideration of the fact that Berkeley claims that only two things exist: minds and ideas, then it will be necessary for the primary as well as the secondary qualities not to exist in the external world, but in the mind of the perceiver.
In the light of the fact therefore that Locke had implied it, since even the mind according to him could put together simple and complex ideas. Which ordinarily contain both primary and secondary qualities, then there is no valid reason why a material object is required for the existence of the primary qualities. One could say therefore that Berkeley only wanted to say what Locke did not say, or could not have finished saying.
3.2.2 On the Nature of Substratum
In an arguably rare moment of skepticism, and perhaps to withhold an assertive position on the nature of the external world behind the primary qualities Locke said exist, Berkeley had withdrawn making bold assertions. Having ascribed to the nature of experience and the senses the abilities that Locke had done, he could not proceed to lay the foundations and the support for primary qualities in the external object, so that modern commentators and historians are able to conveniently categorize him as saying what we perceive is not the physical object behind the primary qualities, but nothing beyond these qualities. We can only go ahead to infer in conformity with experience that there must be some place where these qualities exist together before they are presented to us in experience. This was how he ended up an indirect realist, or a representationalist.
When Berkeley came to the scene however, he showed us that what Locke could have said but did not was that our inference of the external object is not sufficient evidence of its existence, such that since only the primary and secondary qualities can be perceived, then they are the ones that we can validly make claims and so assert existence to. It seemed therefore that Locke was saying tacitly that what exists in the world was primary qualities, and the material behind it, according to him was “that which we know not of” and nothing more than this can be said of it.
Now, granted that Locke had handed over to Berkeley the relevant ropes of his own criticism, it enabled Berkeley to push out of the table of existence, Locke’s “that which I know not of” so he could claim sufficiently that it was God who was the author of the ideas in our minds, making his doctrine of esse est percippii. The same concept of understanding we shall be imposing upon Locke, thus for him that primary and secondary qualities exist, then we can say that their existence is not necessarily dependent upon any notion of substratum. This is seen to be relevant especially in the light of Locke’s inability to say any other thing other than that the primary and secondary qualities must have somewhere in which they subsist. If that is the case, then it is not a necessary criterion that substance must exist before the qualities do, since they are shown to be ideas in the minds of the perceiver both primary and secondary.
The implication will be that while Locke might not affirm God as the origin of his own ideas, as long as he is able to say that even primary qualities are subjective, then Berkeley’s position of subjectivity can be imposed upon him. And for as long as he cannot lay any more claim about the necessary existence of substratum other than that it holds primary and secondary qualities together, then the fact that it can be shown that these qualities exist in the mind of the perceiver kills the necessity raised. So, matter or substance does not require an existence because of the subjectivity of the qualities in Berkeley as much as in Locke.
3.3 My Position on the Issue
While Locke had attempted to articulate his argument on the nature of the existence of both primary and secondary qualities and the material substance he could not deny behind them, it raised questions in his epistemology. For instance he had to explain how substratum, which he could not say much abouts be the “pillar” behind the existence of primary and secondary qualities. This has an implication for Lockean philosophy.
Let us consider his argument in a new light. If it is the case that qualities are nothing but “the ability of an object to cause ideas in our mind”, the implication will be that since it is this object that causes the qualities, then it means that the object from which the qualities emerge pre-suppose the existence of the qualities. For the qualities to exist because they are emissions from the object, then it means this object as a special causal power, and this is the quality. But for the causal power to even be at all, this material object had to first exist. It is because it exists that it is able to cause the ideas that it causes in our minds. Those that Locke claimed are resident in the object which are the primary qualities. It is surprising then that Locke would return to deny existence to the cause of the qualities. From this line of argument, the implication will be that if the object cannot be said to certainly exist, then on what grounds can we say that primary and secondary qualities have a causal base in the external world? We will have no right to say that. And if that is the case, then we might as well be saying that from sensation, there can be no data, and therefore in reflection there can be no ideas.
On a different ground, if Locke claims that the object “causes” ideas in our mind, one might want to take him up on his usage of the word “cause”.
David Hume, in his An Enquiry Concerning Human Understanding had laid down the conditions that must exist before one can say that there is a causal relation between two events: cause and effect. For him, for an event to cause another, there must first exist the condition of spatio-temporal priority which means that the cause must come before the effect. Secondly is the position of spatio-temporal contiguity, which states that cause and effect must be close to each other in space. And then the third condition of spatio-temporal simultaneity which states that cause and effect must be close to each other in time. The final undiscoverable condition of Hume however was the idea of necessary connection which could not be discovered a priori and neither could it be discovered a posteriori leading Hume into the problem of induction. If we are to consider these conditions against Locke’s idea of causation, another problem can be brought out.
For the object to cause ideas which we refer to as qualities, these conditions must be satisfied between both concepts of object and qualities. The condition of spatio-temporal priority has been established already, although it leads Locke into a deeper problem on its own independent of the others. The condition of spatio-temporal contiguity cannot be established. This is because cause: the object and the effect: qualities cannot be observed to be close or far away from each other for the fact that the qualities only obtain in the mind. While the cause (the object) is a mere inference from the external world. The condition of spatio-temporal simultaneity can also not be examined for the simple fact that we cannot observe any notion of time between our perceptions of the effect and be able to supply an inference of matter behind them. The concept of time definitely does not play any part here, since it will only have us saying we know what the material object looks like which Locke was trying not to say. The idea of necessary connection cannot be discovered as well. Because it seems that Locke has taken a reverse step in the light of what Hume’s contention is.
Hume says that because we could observe the causes, we are able to infer and sometimes observe the effects. For Locke however, our perception of the effect (qualities) is what helps us infer the cause: substratum. One can say therefore that Locke’s epistemology is not a relevant account of perception for the reason that it is contrary to experience. And this undermines Locke’s position as an empiricist.
No matter how much strength one says the argument of Berkeley has, it can still be criticized. The fact that Locke had already said that matter is “that which he knows not what” is not sufficient reason to assume that it does not exist. This is an unfair assumption on the part of Berkeley. Locke did not imply he was an idealist in any aspect of his work, otherwise he would not have attempted postulating concepts of primary qualities which are subjective in nature. Although one may still criticize Locke on his saying that they are perceptible mentally since they are ideas. The implication is that Berkley’s idealism is an unfair attempt to push Locke’s materialism to a conclusion that Locke does not agree with.
Locke’s epistemology although considered an adequate theory of perception by the proponents of the position of representationalism that he had established is not devoid of its faults. On one hand it could be shown to be subsumable under the accounts of Berkeley by attempting a synthesis of both positions. But regardless, Berkeley’s position is not an adequate conclusion to which Locke’s argument could be pushed. And on the other hand it was shown to be unable to stand up to the account of causation recognized in Hume.
This shows that Locke’s account although a brilliant contribution, is objectionable especially in the light of post-Lockean accounts.
 Bonjour, Laurence. In Search of Direct Realism. Washington D.C: University of Washington, n.d. p. 3
 Descartes, Rene. "Meditations on First Philosophy." Descartes, Rene. The Philosophical Works of Descartes. Cambridge: Cambridge University Press, 1641. 1-33.
 Group, Taylor and Frances. Philosophy for AS. Frances and Taylor Group, 06 07 2014. p. 24
 Searle, John. Mind. New York: Oxford University Press, 2004.p.16
 Kenny, Anthony. A New History of Western Philosophy: Volume 1: Ancient Philosophy. New York: Oxford University PressInc.,, 2004.
 Ibid: 57
 Anthony Kenny: A New History of Western Philosophy: Volume 1: Ancient Philosophy. Clarendon Press: Oxford. Oxford University Press Inc., New York, 2004. p. 53
 Hume, David. An Enquiry Concerning Human Understanding . Oxford: Oxford University Press, 1902.