The primary purpose of this essay is to critically examine Locke’s theory of perception. This theory of perception is more like a theory of knowledge in which sense experience is the true source as opposed to reason. It is derived from the branch of philosophy called ‘epistemology’ which originated from the Greek word ‘episteme’ meaning knowledge. Knowledge is expressed in propositions but before we can understand any propositions at all, even false ones, we must first have concepts. To understand the meaning of a word already involves having a concept. How do we then acquire the concepts that we have? It was once thought at least some of our concepts are innate. However, suppose that concepts were innate, and then we would have them without ever experiencing any instances. It seems too obvious that no concept of any sensory property is innate. Some concepts have been believed to be innate: for example, the concept of cause and the concept of God.
If the concept of cause is innate, then we would know what the word means, and be in full possession of the concept, without ever having seen causes operating. This seems implausible.
Perhaps the God example seems more plausible, since God, if one exists, is not seen or otherwise perceived, and yet we do seem to possess the concept (though this too has been denied). If we cannot perceive God and nevertheless have the concept, how can we come by it? Is it innate?
We subscribe to John Locke’s alternative theory which explains that concepts are derived from experience. However, despite its merits it has its own shortcoming which this essay’s objective is to point out. John Locke aimed at clearing the ground a little, and removing some of the rubbish that lies in the way to knowledge. Locke hit upon a bold and original interpretation of how the mind works and from this described the kind and extent of knowledge we can expect from the human mind. ‘The scope of our knowledge, Locke said, is limited to, and by our experience(Stumpf, 1977: 273).’
Francis Bacon and Thomas Hobbes say that knowledge should be built on observation, and to this extent they could be called empiricists. They both accepted that the mind is capable of producing certainty of knowledge about nature provided only that the proper method is used. Similarly, Rene Descartes (1594-1650) assumed that there was no problem that human reason could not solve if the correct method was employed. This was the assumption Locke called into critical question, namely, the assumption that the human mind has capabilities that enable it to discover the true nature of the universe. David Hume pushed this critical point even further and asked whether any secure knowledge at all is possible.
Instead of the word ‘concepts’ these philosophers all used the word ‘ideas’ and the problem they undertook to answer was: How do we come by the ideas we have or ever shall have? All the ideas we have or ever shall have, they said come from experience.
Some come through the outer senses, such as sight, hearing, and touch, and from these all our concepts involving the physical world are drawn; and some ideas come from the inner senses, such as experiences of pain and pleasure, feelings of love and hate, pride and remorse, experiencing of thinking and willing. All our concepts are derived from these kinds of experience.
This is the core of Locke’s empiricism and in the following chapters other issues will require further elucidation and these include his refutation of innate ideas, simple and complex ideas, as well as that of primary and secondary qualities. It is equally important that Locke’s analysis of substance and the degrees of knowledge is treated.
However, it is pertinent that we write a brief biography of John Locke, Locke’s empiricism, the meaning of perception and most importantly the problem of perception because it is after the problems have been stated that other chapters will be valuable. We proceed.
THE MAN LOCKE
John Locke was born in 1632 at Wrington, Somerset, and died Seventy-two years later in 1709. He grew up in a puritan home, trained in the virtues of hard work and the love of simplicity. After a thorough training in the classics at the West minister school, Locke became a student at Oxford University where he took the Bachelor’s and Master’s degrees and was appointed Senior Student and later censor of Moral Philosophy. He spent thirty years of his studies of Aristotle’s logic and metaphysics; he was gradually drawn toward the newly developing experimental sciences, being influenced in this direction particularly by Sir Robert Boyle. His scientific interests led him to pursue the study of medicine and in 1674 he obtained his medical degree and was licensed to practices. He also ventured into diplomacy. He actually served in various capacities, eventually becoming the personal physician and confidential adviser to the Earl of Shaftesbury, one of the leading politicians of London. But earlier influences, among them his reading of Descartes’ works while at Oxford, confirmed his desire to devote his creative powers to working out a philosophical understanding of certain problems that perplexed his generation.
He wrote on such diverse topics as The Reasonableness of Christianity, An essay Concerning Toleration, and the Consequences of the Lowering of Interest and Raising the Value of Money indicating his active participation in the public affairs of his day. In 1690, when he was fifty seven-years old, Locke published two books, which were to make him famous as a philosopher and a political theorist: An Essay Concerning Human Understanding and Two Treatises of Civil Government. Although other philosophers before him had written about human knowledge, Locke was the first to produce a full length inquiry into the scope and limits of the human mind. Similarly, others had written important works on political theory, but Locke’s second of the two treatises came at a time when it could shape the thoughts of an era and later affect the course of events. It indicates Locke’s way of combining his practical and theoretical interests and abilities.
Locke decided that before one could move directly into such a subject as the principles of morality and revealed religion, it was necessary we examined our own abilities, and see what our understandings were, or were not fitted to deal with. From this examination Locke eventually composed his Essay on Human Understanding, which became the foundation of empiricism in Britain.
According to Locke, knowledge is restricted to ideas, not platonic ideas or forms, but ideas that are generated by objects we experience thus debunking the claim of the rationalists that reason is the primary source of knowledge (Copleston, 1964: 72).
The origin of ideas is experience, and experience takes two forms, sensation and reflection. Without exception, all our ideas come to us through the sense, whereby we experience the world external to us, and through reflection upon these ideas, which is an experience internal to us. He tried to clarify that we cannot experience the world external to us, and through reflection upon these ideas, which is an experience internal to us. He clarifies that we cannot have the experience of reflection until we have had the experience of sensation. For reflection simply means the mind taking notice of its own operations but its operations begin when the mind is provided with ideas, and these ideas come through the senses (Locke, 1985: 182).
MEANING OF PERCEPTION
Perception is the process by which organisms interpret and organise sensation to produce a meaningful experience of the world. Sensation usually refers to the immediate, relatively unprocessed result of stimulation of sensory receptors in the eyes, ears, nose, tongue, or skin. In practice, sensation and perception are virtually impossible to separate, because they are part of one continuous process (www.wikipedia.com).
PROBLEM OF PERCEPTION
John Locke in his theory of knowledge laid great emphasis on experience as the primary source of indubitable knowledge. However, Locke failed to take into cognizance the fact that, objects of experience are dynamic and fallible. Heraclitus of Ephesus, an ancient Greek philosopher posits that, ‘Things in this world are in a state of flux, constantly changing (Armstrong, 1977: 23).’
Following in this postulation of Heraclitus, how then can our experience or senses grasps reality or true knowledge as the case may be, in a constantly changing world?
In the footsteps of Heraclitus, Socrates through his method of dialectics was able to discover that, true knowledge cannot be derived from perception, relegating it as the least reliable and this is aptly captured in his statement that, ‘Perception does not give us true knowledge; therefore, knowledge cannot be acquired through perception’ (Armstrong, 1977: 24).
Scrutinizing the theory of knowledge by Locke, one will discover that it has a lot of problems to contend with, among whom are, the problems of perception and that of appearance and reality. Though there seems to be a similarity between the former and the latter.
The problem of perception can be said to arise as a result of human state of affairs at a material time. Perceiving a green table in a room may give varying impressions, in different thought, depending on their state at that particular time. In other words, a green table might for instance appear yellow in the eyes of a man suffering from jaundice. Also, the amount and type of light focused on the same green table might give an onlooker the cause to refer to it as purple.
Similarly, the timing of the perception of the green table may also affect its colour. For instance, if the green table is perceived in the night around 10.00pm with the moonlight, the green table might appear black or brown.
Hence, it can be said that, true and infallible knowledge cannot be achieved through this means.
On the issue of appearance and reality, it is pertinent to say at this juncture that, appearance is basically different from reality; hence one can safely say that seeing something as it appears is not enough to conclude that, one has the knowledge of that thing.
When a straight stick or ruler is inside a bowl of water, it will appear to be bent, thus, giving a wrong impression to the onlooker, but in reality, neither the stick nor the ruler is bent, because after removing them from the bowl of water, they look straight again. Should this situation be accepted as the original state of the object? Is it as it appeared to us outside the bowl of water? Or the way they appeared inside of it?
Furthermore, we also experience illusion such as, mirage, where what we see is not real. For instance, when driving on a highway on a sunny afternoon, looking ahead, one will see a pool of water in a distance, and on getting to the spot, the place turns out dry. People are often also victims of hallucinations and they tend to see things which are not actually there. This goes to show the unreliability of senses.
All the instances given earlier are inconvertible facts of our experiences. And they have only buttressed the fact that, experiencing or perceiving things as they are, is not enough justification of the knowledge of that thing. And this cannot be farfetched from the fact that, objects often appear differently to different people or observers at the same time or to some other observers at different times, thus, bringing about incoherent conclusions from all the observers as earlier reiterated. Though, this largely depends on state of affairs, light, physiological position, or state of the observer.
All that had been said above, can tempt one to conclude that, reality cannot be sensed or perceived, or that, we can never know whether our experience is illusory or not, or that sense experience is not a reliable source of knowledge.
Even, we can state here that, issues of knowledge acquisition is in two folds, we have knowledge through experience, and knowledge on the statement of fact, as when one says, ‘all bachelors are unmarried’. But the empiricists reject this on the grounds that, it is not verifiable.
Ludwig Wittgenstein opined that,
‘Such statements, which cannot be verified and disproved, are meaningless, only statements, which can be verified and proved, should be accepted ‘(Scruton, 1981: 137).
By and large, one can see that keen as Locke was on the clarity of knowledge, he did not escape the fatal confounding of sense-knowledge with intellectual knowledge, thereby, making the confusion more confounded, so that one may take not only different, but opposite doctrines, from the premises his theories present. If one follows his work in one set of principles, and develop it to the end, one will find himself in idealism, and if you choose to follow him in another of his thought, you will find yourself in positivism, which it takes reality around us as, the only thing that is, and denies value to the intellect and reason.
Locke, in his conception and origin of ideas, based it on the foundation and background of the empiricists; those ideas are derived from sensation. He recognizes the extreme importance of sensation, which could be seen in his second work. He believed that knowledge originates from two sources; sensation and reflection.
He also asserts that, knowledge is a process of compounding, repeating, comparing, and uniting sensation. But he ran into a problem, which was indeed great, because, he was unable to keep up his thoroughly atomic theory of mind. It is a theory which makes all relations external, they are, as he would say, super-induced upon facts. This makes it impossible to account for any appearance of unity and convention among ideas. He quietly, and without any consciousness of the contradictions involved, introduces certain inherent relations into the structure of the ideas, thereby, further discussing the objective character of sensation in relation to the object which produces it. Locke distinguished simple and complex ideas because he felt, to discuss about ideas intelligently, it will be convenient to distinguish them, as they are matter in the bodies that cause them (Popkin, 1969: 194).
Consequently, one can see that Locke tends to lay down the marks of sensation as passivity and simplicity as the real element in knowledge but Leibniz denies or accepts in a sense different from that of Locke. According to Russell, ‘Reality for Leibniz is not a supernatural yoking of things naturally opposed, and also not a mere accident (Russell, 1971: 82).’
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2. Copleston F. (1964), A History Of Philosophy,
vol 5 New York, Image Books
3. John Locke, (1975), Essay Concerning HumanUnderstanding, Ed. By Peter H. Niddith, Oxford: Claredon Press.
4. Popkin, R (1969), Philosophy Made Simple, New York, Heinemann Publishers.
5. Russell, B (1971), A Critical Exposition of the Philosophy of Leibniz, London, Routledge Publishing Co.
6. Stumpf E.S (1964), Philosophy: History and Problems,New York, Mc Graw-Hill Book Co.
7. Whitehead, A.N (1982), Western Political Thought,Ivor Belere(Ed), London, George Allen and Union Ltd.
1.1 REFUTATION OF INNATE IDEAS
Popkin maintained in Locke’s argument that,
If by this inquiry into the nature of the understanding, I can discover the powers thereof, how far they reach, to what things they are in any degree proportionate, and where they fail us; I suppose it may be of use to prevail with the busy mind of man to be more cautious in meddling with things exceeding its comprehension; to stop when it is at the utmost extent of those things, which upon examination, are found to be beyond the reach of our capacities (Popkin,1969: 193).
In Locke’s Book An Essay Concerning Human Understanding. Book 1 of the Essay, Of Innate Notions is dedicated to refuting the hypothesis that we are born with imprinted or innate ideas and knowledge, something that puts him at odds with the thought of Descartes that he is refuting here. At the time it was widely thought that certain ideas and principles were imprinted on human beings from birth and that these were essential to the stability of religion and morality and I think this is one reason why Locke spends so much time debunking the notion of innateness.
‘It is an established opinion among some men, that there are in the understanding certain innate principles stamped upon the mind of man, which the soul receives in its very first beginning, and brings into the world with it’(Stumpf, 1997: 275). There is more to it than that Locke believed deeply in humanity.
Furthermore, John Locke’s rejection of innate ideas was intimately linked to this project for it is all too easy to claim all sorts of principles as innate in order to maintain the status quo, meaning that people ‘might be more easily governed by, and made useful to some sort of men, who has the skill and office to principle and guide them. Nor is it a small power, it gives one man over another, to have the authority to be the dictator of principles, and teacher of unquestionable truths: and to make a man swallow that for an innate principle which may serve his purpose, who teaches them. ‘If a skillful ruler could convince the people that certain principles are innate, this could take them off from the use of their own reason and judgment, and put them on believing and taking them upon trust without further examination and in this posture of blind credibility, they might be more easily governed’ (Stumpf, 1977: 276).
1.2 OTHERS VIEWS ON THE ARGUMENT OF INNATE IDEAS
There is a genetic issue concerned with the origin of our ideas: where do our beliefs and ideas come from? The empiricists answer of course, we obtain all our ideas from experience, and the rationalists posited that at least some of our ideas are innate.
According to Alvin Goldman, in his paper ‘Innate Knowledge’ he investigates if being innate has any justificatory quality. He comes to the conclusion (within the frame of an existentialist account of justification in terms of a causal connection between the fact that P and the belief that P) that innate principles can indeed be justified just in virtue of being innate. He argues that evolutionary adaptation is a causal connection since being born with a certain belief can be helpful to survive (and the evolutionary process, in his view, would of course favour the true beliefs).
However, such an account of justification is highly controversial and most epistemologists instead hold the view that being innate makes beliefs not justified. We can easily imagine that innate beliefs are false.
Meanwhile, the rationalists hoped to show that the origin of our innate principles somehow guarantees their truth (e.g. in Descartes, God as the origin of innate ideas is perfectly trustworthy), but this attempt was mistaken (www.niu.edu/philosophers/descartes.html). Two problems with innateness as justification will be listed as follows:
(1a) how can we know that an innate belief is really true?
(2a) how can we know that a belief is innate, that is, what kind of intuition accompanies innate beliefs? Both questions are not answered in Goldman’s proposal. Even if a highly reliable mechanism (such as God’s imprinting principles) existed, (1b) they were still not justified in concluding the truth as long as it is not justified in believing that there is such a mechanism applied to a specific believe, (2b) we could never be sure that a belief is innate since our intuition is a bad measure of credibility. The latter was objected by Locke, stating that so-called innate ideas are not clearer perceived than others
Therefore, it will be appropriate to put aside the epistemological issue completely and adapt Stitch’s view that to characterize a piece of knowledge as a priori (as it was often done by the rationalists) is to say something about origin. The term ‘innate knowledge’ according to Stitch was often replaced by ‘innate belief’ to emphasize that justification is not automatically granted. But we should always keep in mind that ‘innate principles’ were one of the cornerstones of the philosophy of continental rationalism, and it is doubtful if innatism could be separated from rationalism at all.
1.3 JOHN LOCKE’S ARGUMENT ON REFUTATION OF INNATE IDEAS
Various arguments will be considered in this essay and one will be more of a response to Locke’s argument by Leibniz.
John Locke considers for example the simple notion that it is not possible for something to both exist and not exist. Locke argues that if such a proposition were innate then every person in every period of history would know and understand this, but this is clearly not the case. If such truths were ‘imprinted’ on us all then we would expect that children and idiots would not only be fully aware of them, but also be able to articulate them. For Locke it makes no sense to imagine both that ideas or knowledge is innate and that we do not know them, thus in his own words: ‘It seems to me a near contradiction to say that there are truths imprinted on the soul, which it perceives or understand not; imprinting if it signify anything, being nothing else but making certain truths to be perceived’ (www.oregonstate.edu/philosophers/locke.html).
Moreover, he goes on to take up the suggestion that innate propositions are only perceived under certain circumstances.
‘To be in the mind and not to be perceived is the same as, anything is not in the mind(Russell, 1971: 80)’. The above statement can be said to be a reaction against the statement of Locke that, ‘if these are not notions, naturally imported, how can they be innate’ (Locke, 1975: 46)? The crux of his argument is that once we start to think in this way it becomes unclear what is meant by innate ideas at all if we are not all aware of them nor able to perceive them can they really be described as innate? Accepting such a view would make it impossible to distinguish between innate ideas that we discover.
HIS SECOND ARGUMENT
Locke takes up at some length the claim that innate propositions are discovered when people come to use reason. For Locke, it makes no sense to describe a truth that is discovered through the use of reason as innate and he constructs a careful argument to back this up, investigating and refuting different interpretations of the claim. He did not go into much detail here, but he goes on to reject the claim that there are innate practical moral principles or that we are born with innate ideas of God, identity or impossibility.
It is by degrees that we acquire ideas, that we learn the terms which are employed to express them, and that we come to express their true connection. The universal consent of mankind in the first argument to certain truths does not prove that these are innate for nobody knows those truths till he hears them from others. For, if they were innate, an innate and unknown truth is a contradiction in terms.
Also, the principles of morals are no more innate than the rest, unless we call the desire for happiness and the aversion to misery, which are, indeed, innate tendencies, but which are not expressions of some truths engraved on the understanding. In this field, universal consent cannot be invoked in any case; for moral ideas vary from nation to nation, from religion to religion. The keeping of contracts, for example, is without dispute one of the most undeniable duties in morality. But,
If u ask a Christian, who believes in rewards and punishments after this life, why a man should keep his word, he will give this a reason: Because God, who has the power of eternal life and death, requires it of us. But if a Hobbist be asked why: he will answer: Because the public requires it and the Leviathan will punish you if you do not. Finally, a pagan philosopher would have answered that the violation of a promise was dishonest, unworthy of the excellence of man, and contrary to his vocation, which is perfect virtue (Locke and Pattison, 1978:29).
Moreover, how can a truth, that is, a proposition, be innate, if the ideas which make up that truth are not? In order that a proposition is innate, certain ideas must be innate: but, ‘excepting perhaps some faint ideas of hunger, warmth and pains, which they may have felt in the mother’s womb, there is not the least appearance that new-born children have any settled ideas’ (Aaron, 1971: 33).
Even the idea of God is not innate; besides the individuals who are called atheists and who are really atheists, there are whole nations who have neither notion nor any term to express it. Therefore, this notion varies infinitely from coarse anthropomorphism to the deism of the philosophers. And even if it was universal and everywhere the same, it would not, on that account, be more innate than the idea of fire; for there is no one who has any idea of God who has not also the idea of fire.
THE THIRD ARGUMENT
On the issue of innate ideas which Locke rejected, the work of Gottfried Leibniz, in his New Essays on Human Understanding will be given consideration. Though, this work of Leibniz was not a critique of Locke’s theory, but rather, is an application of his philosophical conclusions. This argument specifically briefs the position of Leibniz interest on innate ideas. Leibniz was a contemporary philosopher of Locke. Like Locke, Leibniz was very much interested in Descartes’ philosophy. While Locke did not agree with the idea of souls and innate ideas, this is what Leibniz was interested in. Leibniz did not believe in a mechanistic view of the universe. His book on New Essays on Human Understanding consists of two characters engaged in ph