Locke’s Essay
John Locke was a British doctor and philosopher. Locke’s most famous and influential work is the Essay Concerning Human Understanding, published in 1689/90. A central work of the Enlightenment, it is an extremely wide-ranging work, though its primary focus is on epistemological matters. Locke makes this emphasis on epistemology clear in the introduction.
I thought that the first step towards satisfying several inquiries the mind of man was very apt to run into, was, to take a survey of our own understandings, examine our own powers, and see to what things they were adapted. Till that was done I suspected we began at the wrong end, and in vain sought for satisfaction in a quiet and sure possession of truths that most concerned us, whilst we let loose our thoughts into the vast ocean of Being (I.i.7)
That is, a proper examination of our understanding (or cognitive faculties more broadly) will help us, Locke thinks, in getting clearer about both the kinds of inquiry that we might successfully carry out, and the kinds which are hopeless for us. As he puts it just a few paragraphs previously to the text quoted above,
If we can find out how far the understanding can extend its view; how far it has faculties to attain certainty; and in what cases it can only judge and guess, we may learn to content ourselves with what is attainable by us in this state. (I.i.4)
The four books of the Essay thus consider the nature and scope of human knowledge. Book I argues that we have no innate knowledge or ideas. Book II argues that all ideas and knowledge must come from experience. Book III discusses the nature of language, connections between language and ideas, and the role of language in acquiring knowledge. Finally, Book IV examines the nature and limits of knowledge itself, as well is issues concerning probability, faith, and rational belief. Locke here deals with issues familiar from reading Descartes’s Meditations, such as knowledge of an external physical world, and knowledge of God’s existence and features.
Locke’s Ideas
Locke defines the term ‘idea’ in the first book of the Essay.
I must here in the entrance beg pardon of my reader for the frequent use of the word idea, which he will find in the following treatise. It being that term which, I think, serves best to stand for whatsoever is the object of the understanding when a man thinks, I have used it to express whatever is meant by phantasm, notion, species, or whatever it is which the mind can be employed about in thinking; and I could not avoid frequently using it. (I.i.8)
Two things about this definition of ‘idea’. First, Locke uses ‘thinking’ in the same broad sense that Descartes does, to cover not only overt acts of cogitation or judgment but also the kind of mental events or states we more straightforwardly associate with perceptual experience. Second, note the functional definition. Locke doesn’t think he can adequately pick out what it is that actually occurs in the event of ‘having’ an idea. So, even though there is surely some intrinsic character to one’s particular ideas that sets them apart from other kinds of things, Locke is picking out ideas in terms of the role they play in our mental lives, rather than in terms of what they are in and of themselves.
A further complication is that Locke will often use ‘idea’ both for things ‘in’ the mind, such as one’s thoughts themselves, and for what is ‘outside’ the mind, such as properties of objects in the world. This twin use of ‘idea’ makes for tricky reading. For example,
Whatsoever the mind perceives in itself, or is the immediate object of perception, thought, or understanding, that I call idea; and the power to produce any idea in our mind, I call quality of the subject wherein that power is. Thus a snowball having the power to produce in us the ideas of white, cold, and round,—the power to produce those ideas in us, as they are in the snowball, I call qualities; and as they are sensations or perceptions in our understandings, I call them ideas; which ideas, if I speak of sometimes as in the things themselves, I would be understood to mean those qualities in the objects which produce them in us. (II.viii.8)
Locke admits here that he sometimes speaks of ideas as if they were in bodies and not in our minds. Unfortunately, context does not always make this distinction clear and there is perhaps a systemic ambiguity, and not simply carelessness, that is the root cause of this (cf. @bennett2001b, ch.21).
Locke’s Criticism of Innate Ideas
In the introduction to book I of the Essay, after clarifying the status of his project and the importance of asking after the nature and limits of our cognitive faculties, Locke says
I presume it will be easily granted me, that there are such ideas in men’s minds: every one is conscious of them in himself; and men’s words and actions will satisfy him that they are in others. Our first inquiry then shall be,—how they come into the mind. (I.i.8)
Locke then launches into sustained and polemical criticism regarding the supposed origin of ideas or general cognitive principles in the mind itself. This doctrine of innate ideas—‘Nativism’—was a central part of Descartes’s theory of mind and metaphysics and is used by him to account for our knowledge of the essence of body and mind. Locke believes this doctrine is seriously confused and mounts a series of arguments against it. The issue of whether there are any innate ideas became a central point of dispute between so-called ‘empiricist’ and ‘rationalist’ philosophical positions, and continues to be debated today.
Against Strong Nativism & the ‘Argument from Universal Consent’
(I.ii.2-5)
:CUSTOM_ID: against-strong-nativism-the-argument-from-universal-consent-i.ii.2-5
Locke initially states Nativism as follows:
There is nothing more commonly taken for granted than that there are certain principles, both speculative and practical, (for they speak of both), universally agreed upon by all mankind: which therefore, they argue, must needs be the constant impressions which the souls of men receive in their first beings, and which they bring into the world with them, as necessarily and really as they do any of their inherent faculties. (I.ii.2)
Locke argues against a very strong form of nativism here. On this interpretation of nativism human beings are born with a stock of innate ideas, including a grasp of basic metaphysical principles (e.g. ‘whatever is, is; it is impossible for the same thing to both be and not be’). Locke takes the argument for this position to depend on the supposed universal consent to such principles.
- There are some basic truths & principles to which all human beings consent
- There would be no universal consent unless these truths & principles were innate
- ∴ At least some basic truths & principles are innately known
Locke’s criticism of this argument is empirical. He argues that if it were correct then children, the mentally impaired, and members of non-european cultures (i.e. ‘savages’; cf. I.ii.27) would have knowledge of these truths and principles. But, he claims, they obviously do not. So the strong nativist position is false.
Locke might be taken as arguing against a straw man here, but even a philosopher as sophisticated as Descartes seemed to commit himself to something like the strong version of nativism, and thus to the kind of empirical charge which Locke levies. In a letter Descartes says,
if one may conjecture on such an unexplored topic, it seems most reasonable to think that /a mind newly united to an infant’s body is wholly occupied in perceiving in a confused way or feeling the ideas of pain, pleasure, heat, cold and other similar ideas which arise from its union and, as it were, intermingling with the body/. None the less, it has in itself the ideas of God, of itself and of all such truths as are called self-evident, in the same way as adult human beings have these ideas when they are not attending to them; for it does not acquire these ideas later on, as it grows older. I have no doubt that if it were released from the prison of the body, it would find them within itself. (to Hyperaspistes, August 1641, 3:424; my emphasis)
However, this remark of Descartes’s also provides a possible avenue of escape (cf. /Principles/ 8:35). As Descartes points out, despite the possession of innate ideas, young children (and, we may assume, the other cases Locke raises as well) are ‘wholly occupied’ by their senses. Thus they are not in a position to attend to their innate ideas of God, etc. After all, it is one of the chief aims of the Meditations to lead the Meditator away from a reliance on the senses and thus reflect on their own nature as a pure intellect. Descartes’s answer may strain plausibility, but it is not incoherent. So Locke’s appeal to empirical evidence cannot be considered wholly successful (at least against the Cartesian position), since Descartes can reply that the cases Locke cites are all cases where the subject is too “occupied with their senses” to be able to grasp such innate ideas.
Against Weak Nativism (I.ii.6-14)
Locke next considers a weaker form of nativism, in the sense that it does not require the truth of the strong claim to universal assent which the former argument did. Instead, the weaker form of nativism claims only that, once a human being reaches intellectual maturity (or comes ‘to the use of reason’), that person will assent to the relevant truths and principles (I.i.6).
Locke argues that this weaker position is either false or trivial. He distinguishes two versions of the weaker claim:
[that innateness is proved by assent when reason is reached must mean] either that as soon as men come to the use of reason these supposed native inscriptions come to be known and observed by them; or else, that the use and exercise of men’s reason, assists them in the discovery of these principles, and certainly makes them known to them. (I.ii.7)
He dismisses the second version by arguing that, if true, it would entail that not only basic truths of mathematics would be innate but also those truths (‘theorems’) derived from them (I.i.8). Locke finds this conclusion absurd and thus denies the truth of the original claim.
Against the first version of the claim, Locke argues that,
it is evident these maxims are not in the mind so early as the use of reason; and therefore the coming to the use of reason is falsely assigned as the time of their discovery. (I.ii.12)
Hence, (again this is an empirical claim) since children who have acquired the capacity to reason nevertheless cannot be said to know these basic truths, Locke takes the nativist’s claim to be false.
Locke discusses the seeming triviality of the nativist’s claim by considering whether ideas or principles might be innate if they are assented to on ‘first hearing’ (I.i.18). Locke argues that if this is all that is meant by ‘innate’ then nativists will find themselves “plentifully supplied.”
even natural philosophy, and all the other sciences, afford propositions which are sure to meet with assent as soon as they are understood. That “two bodies cannot be in the same place” is a truth that nobody any more sticks at than at these maxims, that “it is impossible for the same thing to be and not to be,” that “white is not black,” that “a square is not a circle,” that “bitterness is not sweetness.” These and a million of such other propositions, as many at least as we have distinct ideas of, every man in his wits, at first hearing, and knowing what the names stand for, must necessarily assent to. (I.ii.18)
This, Locke argues, confuses self-evidence with innateness, and threatens to trivialize the innateness claim by making nearly everything that is basic to knowledge innate.
This problem is not avoided by appealing to an innate capacity to know the kinds of truths or principles advocated by the Nativist.
To say a notion is imprinted on the mind, and yet at the same time to say, that the mind is ignorant of it, and never yet took notice of it, is to make this impression nothing. No proposition can be said to be in the mind which it never yet knew, which it was never yet conscious of. For if any one may; then, by the same reason, all propositions that are true, and the mind is capable ever of assenting to, may be said to be in the mind, and to be imprinted: since, if any one can be said to be in the mind, which it never yet knew, it must be only because it is capable of knowing it; and so the mind is of all truths it ever shall know…So that if the capacity of knowing be the natural impression contended for, all the truths a man ever comes to know will, by this account, be every one of them innate; and this great point will amount to no more, but only to a very improper way of speaking; which, whilst it pretends to assert the contrary, says nothing different from those who deny innate principles. (I.ii.5)
While Locke’s initial expression of his argument seems to rely on the strong claim that there cannot be an idea ‘in’ the mind without one’s being conscious of that idea, his challenge to nativism really concerns the issue of how to credibly make a distinction between innate and learned ideas. Locke seems to think that nativism would be absurd if it should turn out that all true ideas were innate. But he thinks that such an ‘absurd’ position would be entailed by the nativist’s retreat to talk of ‘innateness’ in terms of the mere capacity to know. However, as we shall see in our discussion of Leibniz, not everyone would agree with Locke’s assumption that the class of innate ideas must be smaller than the class of true ideas generally. But this does leave us with a cogent challenge to nativism—viz. how to explain the compatibility between the supposed innateness of ideas and the at least initial appearance of their being (in many cases) learned?
Locke winds up his argument by emphasizing the nativist’s commitment to universal assent, and the denial that anything is added to our knowledge of such supposedly innate ideas and principles by learning, discussion, etc. Here, again, the Cartesian might object that it is compatible with the nativist’s position that many of these innate ideas are very difficult to know clearly because of the influence which the senses exert on our thinking. So, again, Locke’s arguments seem to fall short of their aim, even though they clearly have at least some rhetorical force.
The Origin of Ideas
Since Locke denies that any ideas are innate, he must provide some other account of how the mind comes by its ideas. Locke famously compares the mind to a blank slate or sheet of paper, a ‘tabula rasa’. Since the mind is empty (hence the metaphor of a ‘blank slate’), something other than the mind must be the original source of all of its ideas.
Sensation and Reflection
According to Locke, all of our ideas are derived from experience and experience itself has two sources— sensation and reflection.
First, our Senses, conversant about particular sensible objects, do convey into the mind several distinct perceptions of things, according to those various ways wherein those objects do affect them. And thus we come by those ideas we have of yellow, white, heat, cold, soft, hard, bitter, sweet, and all those which we call sensible qualities; which when I say the senses convey into the mind, I mean, they from external objects convey into the mind what produces there those perceptions. This great source of most of the ideas we have, depending wholly upon our senses, and derived by them to the understanding, I call sensation. (II.i.3)
Sensation is the source of all of our ideas of external qualities, such as hard, soft, cold, hot, bitter, sweet, etc. This source of ideas is contrasted with an inner sense.
Secondly, the other fountain from which experi- ence furnisheth the understanding with ideas is,—the perception of the operations of our own mind within us, as it is employed about the ideas it has got;—which operations, when the soul comes to reflect on and con- sider, do furnish the understanding with another set of ideas, which could not be had from things without. And such are perception, thinking, doubting, believing, rea- soning, knowing, willing, and all the different actings of our own minds;—which we being conscious of, and observing in ourselves, do from these receive into our understandings as distinct ideas as we do from bodies affecting our senses. This source of ideas every man has wholly in himself; and though it be not sense, as having nothing to do with external objects, yet it is very like it, and might properly enough be called internal sense. But as I call the other sensation, so I Call this reflection, the ideas it affords being such only as the mind gets by reflecting on its own operations within itself. (II.i.4)
All of our ideas must come from, or be derived from ideas which come from, these two sources. This content empiricism presents a significant challenge for Locke. He must be able to account for all the ideas which we seem (pre-theoretically at least) to have by tracing them (or their components) to actual experiences in sensation or reflection. I discuss one such subset of ideas below.
Abstract Ideas
Abstract ideas are ideas of ‘general’ or ‘universal’ features of reality. They are the general categories under which particular experienced objects may fall. For example, Locke considers all of our geometric ideas as in the class of abstract ideas. One’s idea of a triangle is an idea of a general class of objects of which there are many distinct kinds. One is able to think of particular shapes (e.g. the particuar three-sided shape drawn on the blackboard, or the three-sided shape one imagines in one’s mind’s eye), but to think of that shape as a triangle is to think of it via the abstract idea of a triangle.
The reason why Locke calls these general ideas ‘abstract’ is that they are abstracted from our ideas of particular objects.
since all things that exist are only particulars, how come we by general terms; or where find we those general natures they are supposed to stand for? Words become general by being made the signs of general ideas: and ideas become general, by separating from them the circumstances of time and place, and any other ideas that may determine them to this or that particular existence. By this way of abstraction they are made capable of representing more individuals than one; each of which having in it a conformity to that abstract idea, is (as we call it) of that sort. (III.iii.6)
The motivation for the abstraction account is due to Locke’s nominalism concerning universals. As the first clause of the first sentence in the quote above indicates, Locke denies that there are any but particulars that exist. If that is correct then how can there be ‘universals’ or ‘general’ entities, that can be ‘instantiated’ in many different particulars (e.g. the way in which it seems that many different possible particulars could instantiate the same shade of red)? Locke’s solution is to say that there are no such universal beings. Instead ideas in one’s mind come to play the role of relating to many different actual or possible particular objects by virtue of some similarity which all those objects share from which one has ‘abstracted’ the idea.
So on Locke’s account, for example, one’s general idea <dog> (as
opposed to one’s idea of a particular dog Fido) is abstracted from one’s
ideas of various particular dogs. The idea comes about via a mental
process – abstraction – by which one focuses only on the features
common to all dogs (of course it is an interesting question as to what
those features are). Given that we obviously do possess such general
ideas, it is incumbent on Locke to provide us with an account of how we
get them.
Locke has two accounts of abstraction, mental separation and mental exclusion, and it is not clear how they relate to one another. According to the mental separation account, we form abstract ideas by mentally distinguishing different characteristics of a perceived object, such as its shape and its color, and recognizing that those characteristics also appear with respect to other objects.
Thus the same colour being observed to-day in chalk or snow, which the mind yesterday received from milk, it considers that appearance alone, makes it a representative of all of that kind; and having given it the name whiteness, it by that sound signifies the same quality wheresoever to be imagined or met with; and thus universals, whether ideas or terms, are made (II.xi.9)
According to the mental exclusion account, we experience a variety of different individuals that resemble each other in various ways and we generate abstract ideas by taking a collection of these individuals and excluding all those properties which they do not, in the relevant respect, share.
There is nothing more evident, than that the ideas of the persons children converse with (to instance in them alone) are, like the persons themselves, only particular…The names they first gave to them are confined to these individuals; and the names of nurse and mamma, the child uses, determine themselves to those persons. Afterwards, when time and a larger acquaintance have made them observe that there are a great many other things in the world, that in some common agreements of shape, and several other qualities, resemble their father and mother, and those persons they have been used to, they frame an idea, which they find those many particulars do partake in; and to that they give, with others, the name man, for example (Here, as nearly everywhere, Locke uses ‘man’ to mean ‘human’; it isn’t confined to the male sex). And thus they come to have a general name, and a general idea. Wherein they make nothing new; but only leave out of the complex idea they had of Peter and James, Mary and Jane, that which is peculiar to each, and retain only what is common to them all. (III.iii.7)
However, it isn’t clear that this form of ‘concept nominalism’ is
coherent. For example, one issue with the account is that it appears
circular. What makes it the case that we can know what to separate or
exclude if we don’t already have the relevant concept? How can I know to
separate the redness of an apple from its shape and then to recognize
and compare that redness to the redness of a fire engine, if I don’t
already have the concept <red>?
Knowledge: Origin vs. Justification
Locke argues that our ideas all originate in experience. Does this mean that we are only justified in our thinking some thought that p when we can trace our ideas to particular experiences? For example, I have the idea of a right triangle as a three sided figure with one 90˚ and two 45˚ angles. But how do I get this idea? Have I ever seen such a triangle? It is not obvious that I have. Even the most precise figure drawings might nevertheless be 1˚ (or less!) inaccurate. It isn’t even clear that I could differentiate between experiences with such small variation. So how is it that I am able to reason about such geometrical figurea, and draw new conclusions concerning them (perhaps I reason out the truth of the Pythagorean theorem), when I cannot trace my ideas of them back to particular experiences?
Similar problems arise for our conception of and reasonings concerning number. We can thus wonder how it is that we get our ideas of such things; from what experiences could they originate.
In addition to this genetic question concerning the origins of our ideas, we might also wonder what it is in virtue of which one is justified in applying such ideas in judgment. How can the empiricist answer this question? The empiricist seems to connect the origins of the idea in experience to the justification of the application of that idea in judgment, but it isn’t clear that this will always hold, especially for ideas connected with experience but in part generated by the mind (such as abstract ideas), or for inferences that go beyond experience (as we’ll see, Hume articulates this kind of worry to great effect)
The rationalist, as we saw with Descartes, has a ready answer to both these questions. According to the rationalist, we are able to deploy ideas in judgment concerning mathematics (or other non-experiential judgments, such as those concerning God) because these ideas are innate (answering the genetic question) and the application of these ideas is justified because (in the case of Descartes) our rational nature has been endowed with these ideas by God, and God is no deceiver.
We’ll see that Leibniz, in the New Essays, uses just this style of argument to try and combat Locke’s polemic concerning innateness.1 But even if Leibniz is unsuccessful in his argument, the empiricist nevertheless has the burden of either explaining the apparent possession of knowledge that is independent of experience in a manner consistent with all of our ideas originating in experience, or explaining the appearance of such knowledge away.