Document – Locke, An Essay Concerning Human Understanding (1690)

Abstract and Keywords

John Locke (1632–1704), the noted English philosopher, scientist, and political theorist, was one of the leading intellectuals of his age and one of the most influential architects of the modern western world. Like his French counterpart René Descartes, Locke came from a respected family and did well in school, directing his studies at Oxford University for a career as a physician. But Locke’s interests were much broader than medicine, and with the assistance of influential friends such as Lord Shaftesbury, he was appointed to a series of governmental positions following the English Civil War and the Glorious Revolution of 1688–1689 that brought William of Orange and Mary to the throne. In his Two Treatises of Civil Government (1690), Locke argued against the Divine Right Theory and began to formulate and espouse a liberal political philosophy based on the notions of natural rights, limited government, and the legitimate right of people to rebel against tyranny.

But although Locke may be best known for his political theories, he was also deeply interested in epistemology and the ways in which people acquire knowledge. In his “Essay Concerning Human Understanding” (1690), Locke expressed frustration with overly abstract forms of thought, which he believed only yielded meaningless and futile discussions of truth and reality. Instead, Locke argued that all knowledge was based on data acquired by the dual process of sensory experience (what he called “sensation”) and subsequent mental thought and analysis (“reflection”). By stressing the importance of observation, the collection of evidence, and inductive reasoning, Locke defined a mode of inquiry called empiricism, which became the foundation for the scientific method so important to the discoveries and technological innovations of the modern world.

In the reading that follows, Locke carefully advances his new theory of human understanding. He begins with his statement of purpose, which he claims is to know and understand the limits of human knowledge. He then proceeds to explain his ideas of “sensation” and “reflection,” as well as his assertion that people are born lacking all innate ideas.

John Locke, The Works of John Locke, a New Edition, Corrected, Vol. 1 (London: Thomas Tegg, 1823): 1–2, 13, 82–84, 86–87, 90–91, 96–98, 99–103, 153–54.

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An inquiry into understanding, pleasant and useful. Since it is the understanding that sets man above the rest of sensible beings, and gives him all the advantage and dominion which he has over them, it is certainly a subject . . . worth our labor to investigate. Like our eyes that allow us to see and perceive all things, understanding takes no notice of itself, and it requires art and pains to set it at a distance, and make it its own object.ⁱ But whatever are the difficulties that lie in the way of this inquiry, whatever it is that keeps us so much in the dark to ourselves, I am sure that all the light we can let in upon our own minds, all the acquaintance we can make with our own understandings, will not only be very pleasant, but bring us great advantage in directing our thoughts in the search of other things. . . .

Useful to know the extent of our comprehension. If, by this inquiry into the nature of the understanding, I can discover its powers, how far they reach, to what things they are in any degree proportionate, and where they fail us, I suppose it may . . . persuade the mind of man to be more cautious in meddling with things exceeding his comprehension, to stop when it is at the utmost extent of its tether, and to sit down in a quiet ignorance of those things, which, upon examination, are found to be beyond the reach of our capacities. . . . 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.

Knowledge of our capacity, a cure of scepticism and idleness. When we know question every thing and disclaim all knowledge because some things are not to be understood. It is of great use to the sailor to know the length of his line,ⁱⁱ [even] though he cannot use it to fathom all the depths of the ocean. It is sufficient that he knows [the line] is long enough to reach the bottom, at such places as are necessary to direct his voyage, and caution him against running upon shoals that may ruin him. Our business here is not to know all things, but those which concern our conduct. If we can find out those measures, whereby a rational creature, put in that state in which man is in this world, may and ought to govern his opinions and actions depending thereon, we need not to be troubled that some other things escape our knowledge.

The way shown how we come by any knowledge, sufficient to prove it not innate. It is an established opinion among some men that there are in the understanding certain innate [inborn] principles, some primary notionsⁱⁱⁱ . . . stamped upon the mind of man, which the soul receives in its very first being and brings into the world with it. It would be sufficient to convince unprejudiced readers of the falseness of this supposition, if I should only show (as I hope I shall in the following parts of this discourse) how men . . . may attain all the knowledge they have without the help of any inborn impressions . . . [or] original notions or principles. . . .

Idea is the object of thinking. Every man being conscious that he thinks, and that which his mind is applied to while thinking being the ideas that are there, it is past doubt that men have in their minds several ideas, such as are those expressed by the words whiteness, hardness, sweetness, thinking, motion, man, elephant, army, drunkenness, and others. It is in the first place then to be inquired, how he comes by them? I know it is an accepted doctrine that men have innate ideas, stamped upon their minds in their very first being. This opinion I have at large examined already, and I suppose what I have already said earlier will be much more easily admitted when I have shown where the understanding may get all the ideas it has, and by what ways and degrees they may come into the mind, for I shall appeal to every one’s own observation and experience.

All ideas come from sensation or reflection. Let us then suppose the mind to be white paper, void of all characters, without any ideas. How comes it to be furnished? From where comes that vast store of ideas which the busy and boundless fancy of man has painted on it with an almost endless variety? From where has it all the materials of reason and knowledge? To this I answer, in one word, from experience. From [experience] all of our knowledge is founded and ultimately derived. Our observation, turned upon either external objects, or upon the internal operations of our minds, is that which supplies our understanding with all the materials of thinking. These two are the fountains of knowledge, from where all the ideas we have, or can naturally have, do spring.

The objects of sensation one source of ideas. First, our senses, familiar with particular material objects, convey to 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. . . . 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.

The operations of our minds the other source of ideas. Secondly, the other fountain from which experience furnishes the [mind] with ideas is the perception of the operations of our own mind within us. . . . These operations [occur] when the mind comes to reflect and consider, [and they] furnish the [mind] with another idea that could not come from external things. And [examples] are perception, thinking, doubting, believing, reasoning, knowing, willing, and all the different notions of our own minds, which we . . . receive into our understandings as distinct ideas. . . . 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 be called internal sense. But as I call the other sensation, so I call this REFLECTION . . . [meaning] that understanding which the mind takes of its own operations. . . .

All our ideas are of the one or the other of these. The understanding seems to me not to have the least glimmering of any ideas which it does not receive from one of these two [sensation and reflection]. External objects furnish the mind with the ideas of sensible [material] qualities, which are all those different perceptions they produce in us; and the mind furnishes the understanding with ideas of its own operations. When we have taken a full survey of them . . . we shall see . . . that we have nothing in our minds which did not come in one of these two ways. Let anyone examine his own thoughts, and thoroughly search into his understanding, and then let him tell me, whether all the original ideas he has there, are any other than of the objects of his senses, or of the operations of his mind, considered as objects of his reflection. . .

The soul begins to have ideas when it begins to perceive. To ask, at what time a man has first any ideas, is to ask, when does he begin to perceive, for having ideas, and perception are the same thing. I know it is an opinion that the soul always thinks, and that it has the actual perception of ideas in itself constantly, as long as it exists; and that actual thinking is as inseparable from the soul as actual extension is from the body; which if true, to inquire about the beginning of a man’s ideas is the same as to inquire after the beginning of his soul. For, by this account, soul and its ideas, as body and its extension, will begin to exist both at the same time. . .

State of child in the mother’s womb. [Anyone] willing . . . to be informed by observation and experience . . . will find few signs of a soul accustomed to thinking in a newborn child, and much fewer [signs] of any reasoning at all. . . . I say, [anyone] who considers this, will perhaps find reason to imagine that a fetus in the mother’s womb differs not much from the state of a vegetable. [The fetus] passes the greatest part of its time without perception or thought, doing very little in a place where it need not seek food, and is surrounded by liquid, always equally soft, and nearly of the same temperature. There the eyes have no light and the ears, so shut up, are not susceptible of sounds, and where there is little or no variety or change of objects to move the senses.

The mind thinks in proportion to the matter it gets from experience to think about. Follow a child from its birth, and observe the alterations that time makes, and you shall find, as the mind by the senses comes more and more to be furnished with ideas, it comes to be more and more awake. It thinks more, the more it has matter to think on. After some time it begins to know the objects which, being most familiar with it, have made lasting impressions. Thus it comes by degrees to know the persons it daily converses with, and distinguishes them from strangers, which are instances and effects of it coming to retain and distinguish the ideas the senses convey to it. And so we may observe how the mind, by degrees, improves and advances to the exercise of those other faculties by enlarging, compounding, and abstracting its ideas, and of reasoning about them, and reflecting upon all these, of which I shall have occasion to speak more hereafter. . . .

Of simple ideas and uncompounded appearances. The better to understand the nature, manner, and extent of our knowledge, one thing is carefully to be observed concerning the ideas we have: some of them are simple, and some are complex. Though the qualities that affect our senses are, in the things themselves, so united and blended, that there is no separation, no distance between them; yet it is plain, the ideas they produce in the mind enter by the senses simple and unmixed. For though the sight and touch often take in from the same object, at the same time, different ideas—as a man sees at once motion and color, [or] the hand feels softness and warmth in the same piece of wax—yet the simple ideas thus united in the same subject are as perfectly distinct as those that come in by different senses. The coldness and hardness which a man feels in a piece of ice are as distinct ideas in the mind as the smell and whiteness of a lily, or as the taste of sugar, or smell of a rose. And nothing can be plainer to a man than the clear and distinct perception he has of those simple ideas, which, being each in itself uncompounded, contains in it nothing but one uniform appearance in the mind, and is not distinguishable into different ideas.

The mind can neither make nor destroy them. These simple ideas, the materials of all our knowledge, are suggested and furnished to the mind only by those two ways above mentioned, namely sensation and reflection. When the understanding is once stored with these simple ideas, it has the power to repeat, compare, and unite them, even to an almost infinite variety, and so can make at pleasure new complex ideas. But it is not in the power of the most exalted wit, or enlarged understanding, by any quickness or variety of thought, to invent or frame even one new simple idea in the mind, which is not taken in by the ways aforementioned; nor can any force of the understanding destroy those that are there. The dominion of man, in this little world of his own understanding, is much the same as it is in the great world of visible things, whereby his power, however managed by art and skill, reaches no farther than to compound and divide the materials that are at his hand. He can do nothing toward making the least particle of new matter, or destroying one atom of what is already in existence. The same inability everyone will find in himself, if he tries to fashion in his understanding one simple idea, not received by his senses from external objects, or by reflection from the operations of his own mind about them. I would have anyone try to imagine any taste which had never touched his palate; or frame the idea of a scent he had never smelled. If he can do this, I will also conclude that a blind man has ideas of colors, and a deaf man true distinct notions of sounds.

Of complex ideas made by the mind out of simple ones. We have hitherto now considered those ideas, in the reception of which the mind is only passive, and which come from sensation and reflection, and which the mind can neither make nor destroy. But as the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed. The acts of the mind, wherein it exerts its power over its simple ideas, are chiefly these three. (1) Combining several simple ideas into one compound one, and thus all complex ideas are made. (2) The second is the bringing together of two ideas, whether simple or complex, and setting them by one another, so as to take a view of them at once, without uniting them into one; by which way it gets all its ideas of relations. (3) The third is separating them from all other ideas that accompany them in their real existence: this is called abstraction, and thus all its general ideas are made. This shows man’s power, and its ways of operation, to be much the same in the material and intellectual world. For the materials in both being such as he has no power over, either to make or destroy, all that man can do is either to unite them together, or to set them by one another, or wholly separate them. I shall here begin with the first of these in the consideration of complex ideas, and come to the other two in their due places. As simple ideas are observed to exist in several combinations united together, so the mind has the power to consider several of them united together as one idea; and that not only as they are united in external objects, but as the mind has joined them together. Ideas thus made up of several simple ones put together, I call complex; such as are beauty, gratitude, a man, an army, the universe; which, though consisting of various simple ideas, or complex ideas made up of simple ones, yet are, when the mind pleases, considered each, by itself, as one entire thing, and signified by one name.

Made voluntarily. In this ability for repeating and joining together its ideas, the mind has great power in varying and multiplying the objects of its thoughts infinitely beyond what sensation or reflection furnished it with; but all this is still confined to those simple ideas which it received from those two sources, and which are the ultimate materials of all its compositions. For simple ideas are all from things themselves, and of these the mind can have no more, nor other than what are suggested to it. It can have no other ideas of sensible qualities than what come from without by the senses, nor any ideas of other kind of operations of thinking than what it finds in itself. But when it has once got these simple ideas, it is not confined barely to observation, and what offers itself from without; it can, by its own power, put together those ideas it has, and make new complex ones, which it never received so united.

Notes

Review

1. How does Locke describe the purpose of knowledge?
2. By initially assuming that human knowledge has its limits, does Locke impose restraints on his investigation? What kind of knowledge is he suggesting lies beyond man’s full comprehension?
3. Locke argues that the human mind is born a blank slate, without any inherent ideas. How does he arrive at the assessment? If this is true, what are some of the implications? How does it compare with Christian theology?
4. According to Locke, “a fetus in the mother’s womb differs not much from the state of a vegetable.” Why? How might this view shape one’s definition of life?
5. If knowledge is ultimately based on “sensation” and “reflection,” how can people best develop and increase their knowledge? What might be the links between Locke’s epistemology and his political theories?

Notes:

(ⁱ) Meaning an objective analysis of the operations of the mind.

(ⁱⁱ) A cord or rope used to measure water depths.

(ⁱⁱⁱ) Ideas that are not based on evidence or reason.