John Locke, Essay Concerning Human Understanding (1690)
Chapter XXIII: Complex ideas of substances
1. The mind is supplied with many simple ideas, which come to it through the senses from outer things or through reflection on its own activities. Sometimes it notices that a certain number of these simple ideas go constantly together, and it presumes them to belong to one thing; and—because words are suited to ordinary ways of thinking and are used for speed and convenience—those ideas when united in one subject are called by one name. Then we carelessly talk as though we had here one simple idea, though really it is a complication of many ideas together. What has happened in such a case is that, because we can’t imagine how these simple ideas could exist by themselves, we have acquired the habit of assuming that they exist in (and result from) some substratum, which we call substance. [‘Substratum’ = ‘what underlies’ = something that serves as the basis or foundation of something else.]
2. So that if you examine your notion of pure substance in general, you’ll find that your only idea of it is a supposition ofan unknown support of qualities that are able to cause simple ideas in us—qualities that are commonly called ‘accidents’.
If anyone were asked ‘What is the subject in which colour or weight inheres?’, he would have to reply ‘In the solid extended parts’; and if he were asked ‘What does that solidity and extension inhere in?’, he wouldn’t be in a much better position than the Indian philosopher who said that the world was supported by a great elephant, and when asked what the elephant rested on answered ‘A great tortoise’. Being further pressed to know what supported the broad-backed tortoise, he replied that it was something he knew not what. So too here, as in all cases where we use words without having clear and distinct ideas, we talk like children who, being asked ‘What’s this?’ about something they don’t recognize, cheerfully answer ‘It’s a thing’. Really all this means, when said by either children or adults, is that they don’t know what it is, and that ‘the thing’ they purport to know and talk about isn’t something of which they have any distinct idea at all—they are indeed perfectly in the dark about it.
So the idea of ours to which we give the general name ‘substance’, being nothing but the supposed but unknown support of those qualities we find existing and which we imagine can’t exist ‘sine re substante’ — that is, without something to support them — we call that support substantia; which, according to the true meaning of the word, is in plain English standing under or upholding. [‘Sub’ is Latin for ‘under’, and ‘stans’ is Latin for ‘standing’; so ‘substans’ (English ‘substance’) literally means something that stands under something.]
3. In this way we form an obscure and relative idea of substance in general. (…) From this we move on to having ideas of various sorts of substances, which we form by collecting combinations of simple ideas that we find in our experience tend to go together and which we therefore suppose to flow from the particular internal constitution or unknown essence of a substance. Thus we come to have the ideas of a man, horse, gold, water, etc. If you look into yourself, you’ll find that your only clear idea of these sorts of substances is the idea of certain simple ideas existing together.
It is the combination of ordinary qualities observable in iron, or a diamond, that makes the true complex idea of those kinds of substances—kinds that a smith or a jeweller commonly knows better than a philosopher does. Whatever technical use he may make of the term ‘substance’, the philosopher or scientist has no idea of iron or diamond except what is provided by a collection of the simple ideas that are to be found in them—with •one further ingredient. complex ideas of substances are made up of those simple ideas plus •the confused idea of some thing to which they belong and in which they exist. So when we speak of any sort of substance, we say it is a thing having such or such qualities: body is a thing that is extended, shaped, and capable of motion;•spirit, a thing that can think; and we say that hardness and power to attract iron are qualities to be found in a loadstone,·conceived of as a thing containing these qualities·. [Loadstone is a kind of rock that is naturally magnetic.] These and similar ways of speaking show that the substance is always thought of as some thing in addition to the extension, shape, solidity, motion, thinking, or other observable ideas, though we don’t know what it is. [Locke uses •‘spirit’, as he does ‘soul’, to mean merely ‘thing that thinks’ or ‘thing that has mental properties’. It doesn’t mean something spiritual in any current sense of the term.]
4. So when we talk or think of any particular sort of corporeal substances—e.g. horse, stone, etc.—although our idea of it is nothing but the collection of simple ideas of qualities that we usually find united in the thing called ‘horse’ or ‘stone’, still we think of these qualities as existing in and supported by some common subject; and we give this support the name ‘substance’, though we have no clear or distinct idea of what it is. We are led to think in this way because we can’t conceive how qualities could exist unsupported or with only one another for support.
5. The same thing happens concerning the operations of the mind—thinking, reasoning, fearing, etc. These can’t exist by themselves, we think, nor can we see how they could belong to body or be produced by it; so we are apt to think that they are the actions of some other substance, which we call ‘spirit’. We have as clear a notion of the substance of •spirit as we have of •body. The latter is supposed (without knowing what it is) to be •the substratum of those simple ideas that come to us from the outside, and the former is supposed (still not knowing what it is) to be •the substratum of the mental operations we experience within ourselves. Clearly, then, we have as poor a grasp of the idea of bodily substance as we have of spiritual substance or spirit. So we shouldn’t infer that there is no such thing as spirit because we have no notion of the substance of spirit, any more than we should conclude that there is no such thing as body because we have no clear and distinct idea of the substance of matter.
6. Whatever the secret, abstract nature of substance in general may be, therefore, all our ideas of particular sorts of substances are nothing but combinations of simple ideas co-existing in some unknown cause of their union. We represent particular sorts of substances to ourselves through such combinations of simple ideas, and in no other way. They are the only ideas we have of the various sorts of things—the sorts that we signify to other people by means of such names as ‘man’, ‘horse’, ‘sun’, ‘water’, ‘iron’. Anyone who hears such a word, and understands the language, forms in his mind a combination of those simple ideas that he has found—or thinks he has found—to exist together under that name; all of which he supposes to rest in and be fixed to that unknown common subject that doesn’t inhere in anything else in its turn. Consider for instance the idea of the sun: it is merely a collection of the simple ideas, bright, hot, roundish, having a constant regular motion, at a certain distance from us—and perhaps a few others, depending on how accurately the owner of the idea has observed the properties of the sun.
7. The most perfect idea of any particular sort of substance results from putting together most of the simple ideas that do exist in it—·i.e. in substances of that sort·—including its active powers and passive capacities. (These are not simple ideas, but for brevity’s sake let us here pretend that they are.) Thus the complex idea of the substance that we call a loadstone has as a part the power of attracting iron; and a power to be attracted by a loadstone is a part of the complex idea we call ‘iron’. These powers are counted as inherent qualities of the things that have them. Every substance is as likely, through the powers we observe in it, (a) to change the perceptible qualities of other subjects as (b) to produce in us those simple ideas that we receive immediately from it. When (b) happens with fire (say), our senses perceive in fire its heat and colour, which are really only the fire’s powers to produce those ideas in us. When (a) happens, we also learn about the fire because it acts on us mediately [= ‘through an intermediary’] by turning wood into charcoal and thereby altering how the wood affects our senses. . . . In what follows, I shall sometimes include these powers among the simple ideas that we gather together in our minds when we think of particular substances. Of course they aren’t really simple; but they are simpler than the complex ideas of kinds of substance, of which they are merely parts.
8. It isn’t surprising that powers loom large in our complex ideas of substances. We mostly distinguish substances one from another through their secondary qualities, which make a large part of our complex ideas of substances . (Our senses will not let us learn the sizes, textures, and shapes of the minute parts of bodies on which their real constitutions and differences depend; so we are thrown back on using their secondary qualities as bases for distinguishing them one from another.) And all the secondary qualities, as has been shown ·in viii·, are nothing but powers. . . .
9. The ideas that make our complex ideas of bodily substances are of three sorts. First, the ideas of the primary qualities of things, including the size, shape, number, position, and motion of the parts of bodies. We discover these by our senses, but they are in the bodies even when we don’t perceive them. Secondly, the sensible [= ‘perceptible’] secondary qualities. They depend on the primary qualities, and are nothing but the powers that bodies have to produce certain ideas in us through our senses. These ideas are not in the things themselves except in the sense that a thing is ‘in’ its cause. Thirdly, when we think that one substance can cause an alteration in the primary qualities of another, so that the altered substance would produce in us different ideas from what it did before, we speak of the active powers of the first substance and the passive powers of the second. We know about the powers of things only through sensible simple ideas. For example, whatever alteration a loadstone has the power to make in the minute particles of iron, we wouldn’t suspect that it had any power to affect iron if that power weren’t revealed by how the loadstone makes the iron particles move. I have no doubt that bodies that we handle every day have powers to cause thousands of changes in one another — powers that we never suspect because they never appear in sensible effects.
10. So it is proper that powers should loom large in our complex ideas of substances. If you examine your complex idea of gold, you’ll find that several of the ideas that make it up are only ·ideas of· powers. For example, the power of being melted without being burned away, and the power of being dissolved in aqua regia [a mixture of nitric and hydrochloric acids]—these ideas are as essential to our complex idea of gold as are its colour and weight. Indeed, colour and weight when properly understood turn out also to be nothing but powers. For yellowness is not actually in gold, but is a power that gold has, when placed in proper light, to produce a certain idea in us through our eyes. Similarly, the heat that we can’t leave out of our idea of the sun is no more really in the sun than is the white colour it gives to wax. These are both equally powers in the sun, which operates on a man—through the motion and shape of its sensible parts—so as to make him have the idea of heat; just as it operates on wax so as to make it capable of producing in a man the idea of white.
11. If our senses were sharp enough to distinguish the minute particles of bodies and the real constitution on which their sensible qualities depend, I am sure they would produce in us ideas quite different from the ones they now produce; the yellow colour of gold, for example, would be replaced by an admirable texture of parts of a certain size and shape. Microscopes plainly tell us this; for what to our naked eyes produces a certain colour is revealed through a microscope to be quite different. Thus sand or ground glass, which is opaque and white to the naked eye, is transparent under a microscope; and a hair seen this way loses its former colour and is mostly transparent, with a mixture of bright sparkling colours like the ones refracted from a diamond. Blood to the naked eye appears all red; but when its lesser parts are brought into view by a good microscope, it turns out to be a clear liquid with a few red globules floating in it. We don’t know how these red globules would appear if glasses could be found that would magnify them a thousand or ten thousand times more.
12. God in his infinite wisdom has given us senses, faculties, and organs that are suitable for the conveniences of life and for the business we have to do here. Senses enable us to know and distinguish things, and to examine them in enough detail to be able to make use of them and in various ways accommodate them to our daily needs. insight into their admirable structures and wonderful effects goes far enough for us to admire and praise the wisdom, power, and goodness of their author. . . . But it seems that God didn’t intend that we should have a perfect, clear, and adequate knowledge of things; and perhaps no finite being can have such knowledge. faculties, dull and weak as they are, suffice for us to discover enough in created things to lead us to •the knowledge of the creator, and •the knowledge of our duty; and we are also equipped with enough abilities to •provide for the conveniences of living. These are our business in this world. But if our senses were made much keener and more acute, the surface appearances of things would be quite different for us, and, I’m inclined to think that this would be inconsistent with our survival—or at least with our well-being—in this part of the universe that we inhabit. Think about how little we are fitted to survive being moved into air not much higher than the air we commonly breathe—that will give you reason to be satisfied that on this planet that has been assigned as our home God has suited our organs to the bodies that are to affect them, and vice versa. If our sense of hearing were merely one thousand times more acute than it is, how distracted we would be by perpetual noise! Even in the quietest retirement we would be less able to sleep or meditate than we are now in the middle of a sea-battle. If someone’s eyesight (the most instructive of our senses) were a thousand or a hundred thousand times more acute than it is now through the best microscope, he would be able to see with his naked eyes things several million times smaller than the smallest object he can see now; ·and this would have •a good result and •a bad one·. •It would bring him nearer to discovering the texture and motion of the minute parts of corporeal things, and he would probably get ideas of the internal structures of many of them. But then•he would be in a quite different world from other people: nothing would appear the same to him as to others; the visible ideas of everything would be different. So that I don’t think that he could converse with others concerning the objects of sight, or communicate in any way about colours, their appearances being so wholly different.
[The section continues with further remarks about the disadvantages of having ‘such microscopical eyes (if I may so call them)’. It ends thus:] Someone who was sharp-sighted enough to see the arrangement of the minute particles of the spring of a clock, and observe the special structure and ways of moving on which its elastic motion depends, would no doubt discover something very admirable. But if his eyes were so formed that he couldn’t tell the time by his clock, because he couldn’t from a distance take in all at once the clock-hand and the numerals on the dial, he wouldn’t get much advantage from the acuteness of his sight: it would let him in on the structure and workings of the parts of the machine while also making it useless to him!
[In section 13—an admitted interruption of the main line of thought—Locke remarks that the structure of our sense organs is what sets limits to what we can perceive in the material world, and offers his ‘extravagant conjecture’ about ‘Spirits’, here meaning something like ‘angels’. Assuming that they ‘sometimes’ have bodies, angels may be able to alter their sense organs at will, thus being able to perceive many things that we can’t. Locke can’t hide his envy about this, though he says that ‘no doubt’ God has good reasons for giving us sense-organs that we cannot flex at will, like muscles.]
14. Each of our ideas of a specific kind of substances is nothing but a collection of simple ideas considered as united in one thing. These ideas of substances, though they strike us as simple and have simple words as names, are nevertheless really complex and compounded. Thus the idea that an Englishman signifies by the name ‘swan’, is white colour, long neck, red beak, black legs, and webbed feet, and all these of a certain size, with a power of swimming in the water, and making a certain kind of noise — and perhaps other properties as well, for someone who knows a lot about this kind of bird— all united in one common subject.
15. Besides the complex ideas we have of •material sensible substances, we can also form the complex idea of an•immaterial spirit. We get this through the simple ideas we have taken from operations of our own minds that we experience daily in ourselves, such as thinking, understanding, willing, knowing, and power of beginning motion, etc. all co-existing in some substance. By putting these ideas together, we have as clear a perception and notion of immaterial substances as we have of material ones. For putting together the ideas of •thinking and •willing and •the power of starting or stopping bodily motion, joined to substance, of which we have no distinct idea, we have the idea of an•immaterial spirit; and by putting together the ideas of •solid parts that hold together, and •a power of being moved, joined with substance, of which likewise we have no positive idea, we have the idea of •matter. [Here ‘positive’ contrasts with ‘relative’. The idea of substance in general is relative because it is only the idea of whatever-it-is that relates to qualities by upholding and uniting them.]
The one is as clear and distinct an idea as the other, the ideas of thinking and moving a body being as clear and distinct as the ideas of extension, solidity, and being moved. For our idea of substance is equally obscure, or none at all, in both: It is merely a supposed I know not what, to support qualities. Those who believe that our senses show us nothing but material things haven’t thought hard enough! When you think about it, you’ll realize that every act of sensation gives us an equal view of both parts of nature, the corporeal and the spiritual [= ‘the bodily and the mental’]. For while I know by seeing or hearing etc. that there is some bodily thing outside me that is the object of that sensation, I know with even more certainty that there is some spiritual being within me that sees and hears. This seeing and hearing can’t be done by mere senseless matter; it couldn’t occur except as the action of an immaterial thinking being.
16. All that we know of body is contained in our complex idea of it as extended, shaped, coloured, and having other sensible qualities; and all this is as far from the idea of the substance of body as we would be if we knew nothing at all. And although we think we are very familiar with matter, and know a great deal about many of its qualities, it may turn out that our basic ideas of •body are no more numerous, and no clearer, than our basic ideas of •immaterial spirit.
17. The basic ideas that we have that apply to body and not to spirit are •the holding together of parts that are solid and therefore separable, and •a power of causing things to move by colliding with them. Bodies also have shapes, but shape is merely a consequence of finite extension.
18. The ideas we have belonging exclusively to spirit are•thinking and •will (which is the power of putting body into motion by thought) and •liberty. Whereas a body can’t help setting in motion a motionless body with which it collides, the mind is at liberty to put bodies into motion or refrain from doing so, as it pleases. The ideas of •existence, •duration, and •mobility are common to both body and spirit.
19. It shouldn’t be thought strange that I attribute mobility to spirit. Spirits, like bodies can only operate where they are; we find that a single spirit operates at different times in different places; so I have to attribute change of place to all finite spirits (I’m not speaking of ·God·, the infinite spirit, here). For my soul [= ‘spirit’ = ‘mind’] is a real thing just as much as my body is, and is equally capable of changing its distance from any other ·spatially located· being; and so it is capable of motion. . . .
20. Everyone finds in himself that his soul •can think, will, and operate on his body in the place where that body is, but •cannot operate on a body or in a place a hundred miles away. You can’t imagine that your soul could think or move a body in Oxford while you are in London, and you have to realize that your soul, being united to your body, continually changes its location during the whole journey between Oxford and London, just as does the coach or horse that you ride on—so I think it can be said to be truly in motion throughout that journey. If that isn’t conceded as giving a clear idea enough of the soul’s motion, you will get one from ·the thought of· its being separated from the body in death; for it seems to impossible that you should think of it as •leaving the body while having no idea of •its motion.
[In section 21 Locke discusses a scholastic reason for denying that souls or spirits can move, and derisively challenges its supporters ‘to put it into intelligible English’. He concludes:] Indeed motion cannot be attributed to God—not because he is an immaterial spirit but because he is an infinite one.
22. Let us compare our complex idea of immaterial spirit with our complex idea of body, and see whether one is more obscure than the other—and if so, which. idea of body, I think, is that of an extended solid substance, capable of transferring motion by impact; and our idea of soul or immaterial spirit is ·the idea· of a substance that thinks, and has a power of making a body move, by willing or thought.
Which of these is more obscure and harder to grasp? I know that people whose thoughts are immersed in matter, and have so subjected their minds to their senses that they seldom reflect on anything that their senses can’t reach, are apt to say that they can’t comprehend a thinking thing. Perhaps they can’t, but then if they think hard about it they’ll realize that they can’t comprehend an extended thing either.
23. If anyone says ‘I don’t know what it is that thinks in me’, he means that he doesn’t know what the substance is of that thinking thing. I respond that he has no better grasp of what the substance is of that solid thing. If he also says ‘I don’t know how I think’, I respond that he also doesn’t know how he is extended—that is, how the solid parts of body cohere together to make extension. I shall discuss the cohesion problem—the problem of explaining how portions of matter hang together to compose planets or pebbles or grains of sand—from here through to the end of section 27·. The pressure of the particles of air may account for the cohesion of some parts of matter that are bigger than the particles of air and have pores that are smaller than those particles; but that can’t explain the coherence of the particles of air themselves. Whatever holds them together, it isn’t the pressure of the air! And if the pressure of any matter that is finer than the air—such as the ether—can unite and hold together the parts of a particle of air (as well as of other bodies), it still can’t make bonds for itself and hold together the parts that make up every least particle of that materia subtilis [= ‘extra-fine matter’]. Thus, however ingeniously we develop our explanation of how the parts of perceptible bodies are held together by the pressure of other imperceptible bodies ·such as the particles of the ether·, that explanation doesn’t extend to the parts of the ether itself. The more success we have in showing that the parts of other bodies are held together by the external pressure of the ether, and can have no other conceivable cause of their cohesion and union, the more completely we are left in the dark about what holds together the parts of each particle of the ether itself. We can’t conceive of those particles as not having parts, because they are bodies, and thus divisible; but we also •can’t conceive of how their parts cohere, because the explanation of how everything else coheres cannot be applied to them.
24. ·The foregoing argument shows that even if pressure from the ether could explain the cohesion of most bodies, it leaves unexplained the cohesion of the particles of the ether itself·. But in fact pressure, however great, from a surrounding fluid ·such as the ether cannot be what causes the cohesion of the solid parts of matter. Such a pressure might prevent two things with polished surfaces from moving apart in a line perpendicular to those surfaces,. . . .but it can’t even slightly hinder their pulling apart in a line parallel to those surfaces—·I shall call this a ‘lateral motion’. The surrounding fluid is free to occupy each part of space that is deserted through such a lateral motion; so it doesn’t resist such a motion of bodies joined in that way, any more than it would resist the motion of a body that was surrounded on all sides by that fluid and didn’t touch any other body. And therefore, if there were no other cause of cohesion ·than this surrounding-fluid one·, all parts of ·all· bodies would be easily separable by such a lateral sliding motion. So it is no harder for us to have a clear idea of how the soul thinks than to have one of how body is extended. For the •extendedness of body consists in nothing but the •union and cohesion of its solid parts, so we shall have a poor grasp of the extension of body when we don’t understand the union and cohesion of its parts; and we don’t understand that, any more than we understand what thinking is and how it is performed.
25. Most people would wonder how anyone should see a difficulty in what they think they observe every day. ‘Don’t we see the parts of bodies stick firmly together? Is there anything more common? And what doubt can there be made of it?’ And similarly with regard to thinking and voluntary motion: ‘Don’t we experience it every moment in ourselves? So can it be doubted?’ The matter of fact is clear, I agree, but when we want to look more closely and think about how it is done, we are at a loss both about extension and about thought. . . .
26. The little bodies that compose the fluid we call ‘water’ are so extremely small that I have never heard of anyone claiming to see their distinct size, shape, or motion through a microscope (and I’ve heard of microscopes that have mag- nified up to a hundred thousand times, and more). And the particles of water are also so perfectly loose one from another that the least force perceptibly separates them. Indeed, if we think about their perpetual motion we must accept that they don’t cohere with another; and when a sharp cold comes they unite, they consolidate, these little atoms cohere, and they can’t be separated without great force. Something we don’t yet know—and it would be a great discovery—is what the bonds are that tie these heaps of loose little bodies
together so firmly, what the cement is that sticks them so tightly together ·in ice·. But someone who made that discovery would still be long way from ·solving the generalproblem·, making intelligible the extension of body (which is the cohesion of its solid parts). For that he would need to show how the parts of those bonds—or of that cement, or of the least particle of matter that exists—hold together. It seems, then, that this primary and supposedly obvious quality of body, ·extension·, turns out when examined to be as incomprehensible as anything belonging to our minds, and that it is as hard to conceive a solid extended substance as it is to conceive a thinking immaterial one. . . .
27. Here is a further difficulty about solving the cohesion problem through an appeal to surrounding pressures. Let us suppose that matter is finite (as no doubt it is). Now think about the outermost bounds of the universe, and ask yourself:
What conceivable hoops, what bond, can hold this unified mass of matter together with a pressure from which steel must get its strength and diamonds their hardness and indissolubility?
If matter is finite, it must have boundaries, and there must be something that stops it from scattering in all directions. If you try to avoid this ·latest· difficulty by supposing that the material world is infinite in extent, ask yourself what light you are throwing on the cohesion of body—whether you are making it more intelligible by relying on the most absurd and incomprehensible of all suppositions. So far is our ·idea of· the extension of body (which is nothing but the cohesion of solid parts) from being clearer or more distinct when we enquire into the nature, cause, or manner of it, than is the idea of thinking!
28. Another idea that we have of body is ·the idea of· the power of transferring motion by impact: and of our souls ·the idea of· the power of exciting motion by thought. Everyday experience clearly provides us with these two ideas, but here again if we enquire how each power is exercised, we are equally in the dark. In the most usual case of motion’s being communicated from one body to another through impact, the former body loses as much motion as the other acquires; and the only conception we have of what is going on here is that motion passes out of one body into the other. That seems to me to be as obscure and inconceivable as how our minds move or stop our bodies by thought, which we every moment find they do. Daily experience provides us with clear evidence of motion produced by impact, and of motion produced by thought; but as for how this is done, we are equally at a loss with both. So that when we think about •the communication of motion, whether by body or by spirit, •the idea of it that is involved in spirit-as-mover is at least as clear as •the one involved in body-as-mover. And if we consider the active power of moving (called ‘motivity’ ·in xxi.73·), it is much clearer in spirit than body. Place two bodies at rest side by side; they give us no idea of a power in the one to move the other, except through a borrowed motion. The mind, on the other hand, every day gives us ideas of an active power of moving bodies. This gives us reason to think that active power may be the proper [here = ‘exclusive’]attribute of spirits, and passive power the proper attribute of matter. If that is so, then created spirits are not totally other than matter, because as well as being active (as matter isn’t) they are also passive (as matter is). Pure spirit, namely God, is only active; pure matter is only passive; and beings·like us· that are both active and passive may be judged to involve both. . . .
29. In conclusion: Sensation convinces us that there are solid extended substances, and reflection that there are thinking ones. Experience assures us that one has a power to move body by impact, the other by thought. That much is sure, and we have clear ideas of it; but we can’t go any further. If we start asking about nature, causes, and manner ·of operation·, we see no more clearly into the nature of extension than we do into the nature of thinking. It is no harder to conceive how a substance that we don’t know should by thought set body into motion, than how a substance that we don’t know should by impact set body into motion. . . .
[In sections 30–31 Locke sums up the results of the last few sections, re-emphasizing that the idea of a thinking substance is not less respectable than that of an extended substance. He concludes section 31 with a new difficulty about the latter:] Nothing in our notion of spirit is more perplexed, or nearer a contradiction, than something that the very notion of body includes in it, namely the infinite divisibility of any finite extended thing. Whether we accept this or reject it, we land ourselves in consequences that we can’t explain or make consistent within our thought—consequences that carry greater difficulty, and more apparent absurdity, than anything that follows from the notion of an immaterial knowing substance.
[In section 32 Locke starts by rehearsing the arguments he has given for the view that ‘we have as much reason to be satisfied with our notion of immaterial spirit as with our notion of body, and of the existence of the one as well as of the other’. He then launches, without announcing that he is doing so, into a new issue: is a human being an extended thing that thinks, or rather a pair of things of which one is extended and the other thinks?]
It is no more a contradiction that •thinking should exist separate and independent from solidity than that •solidity should exist separate and independent from thinking. Thought and extension are simple ideas, independent one from another; and we are as entitled to allow •a thinking thing without solidity as we are •a solid thing without thinking. It may be hard to conceive how thinking could occur without matter, but it’s at least as hard to conceive how matter could think. Whenever we try to get beyond our simple ideas, to dive deeper into the nature of things, we immediately fall into darkness and obscurity, perplexity and difficulties. But whichever of these complex ideas is clearer, that of body or that of immaterial spirit, each is evidently composed of the simple ideas that we have received from sensation or reflection. So are all our other ideas of substances, even that of God himself.
[In section 33 Locke develops that last remark, contending that we can build up our idea of God as infinitely powerful, wise, etc. through a general procedure that he illustrates with an example in section 34.]
34. If I find that I know a few things, some or all of them imperfectly, I can form an idea of knowing twice as many; which I can double again, ·and so on indefinitely·, just as I can generate an endless series of numbers by repeated doubling. In that way I can enlarge my idea of knowledge by extending its coverage to all things existing or possible. And I can do the same with regard to knowing them more perfectly, thus forming the idea of infinite or boundless knowledge. The same may also be done for power. . . .and also for the duration of existence. . . . We form the best idea of God that our minds are capable of, by •taking simple ideas from the operations of our own minds (through reflection) or from exterior things (through our senses) and •enlarging them to the vastness to which infinity can extend them.
35. It is infinity—joined to existence, power, knowledge, etc.—that makes our complex idea of God. Although in his own essence (which we don’t know, any more than we know the real essence of a pebble, or of a fly, or of ourselves) God may be simple and uncompounded, still our only idea of him is a complex one whose parts are the ideas of existence, knowledge, power, happiness, etc.—all this infinite and eternal. . . .
36. Apart from infinity, there is no idea we attribute to God that isn’t also a part of our complex idea of other Spirits [here = something like ‘angels’]. We can attribute to Spirits only ideas that we get from reflection; and we can differentiate them ·from God on one side, and from us on the other· only through differences in the extent and degree of knowledge, power, duration, happiness, etc. that each has. Here is another bit of evidence that we are confined to the ideas that we receive from sensation and reflection: even if we think of·unembodied· Spirits as ever so much, even infinitely, more advanced than bodies are, we still can’t have any idea of how they reveal their thoughts one to another. We have to use physical signs and particular sounds; they are the best and quickest we are capable of, which makes them the most useful we can find. Of course unembodied Spirits must have also a more perfect way of communicating their thoughts than we have; but of such immediate communication we have no experience in ourselves, and consequently no notion at all.
37. Now we have seen what kind of ideas we have of substances of all kinds, what they consist in, and how we came by them. All this, I think, makes three things very evident. 1. All our ideas of the various sorts of substances are nothing but collections of simple ideas, together with a supposition of something to which they belong and in which they exist, though we have no clear distinct idea at all of this supposed something.
2 All the simple ideas which—when thus united in one common substratum—make up our complex ideas of various sorts of substances are received from sensation or reflection. Even •those extremely familiar ideas that apply to almost everything—·such as the ideas of time, motion, body, thought, feeling·—have such simple ideas of sensation and reflection as their only ingredients. So do •the ideas that seem furthest from having any connection with us, and that infinitely surpass anything we can perceive in ourselves by reflection or discover by sensation in other things. Even those ideas must be constructed out of the simple ideas that we originally received from sensation or reflection. This is clearly the case with respect to the complex ideas we have of angels, and especially our idea of God.
3 Most of the simple ideas that make up our complex ideas of substances are really only ·ideas of· powers, however apt we are to think of them as ·ideas of· positive qualities. [Here again ‘positive’contrasts with ‘relative’.] For example, most of the ideas that make our complex idea of gold are yellowness, great weight, ductility, fusibility and solubility in aqua regia, etc. all united together in an unknown substratum; and these are all ideas of gold’s relations to other substances. ·To be heavy is to have a power to outweigh other things; to be yellow is to have a power to cause certain visual sensations in human observers·. [Ductility is the ability to be drawn out into a thin wire, and fusibility is the ability to melt when hot; neither of which is a relation to other substances. Perhaps Locke has a different thought at work here, not properly expressed: he may be contrasting ‘positive’ qualities not only with relative qualities but also with conditional ones. Attributing a power to something is asserting a conditional about it—If it is heated, it will melt. A positive quality such as squareness isn’t like that: the thing justis square, and ‘if’ doesn’t come into it.] These powers depend on the real and primary qualities of the gold’s internal constitution; they are what give it its power to operate on other substances and to be operated on by them; but the powers aren’t really in the gold considered purely in itself.
originally posted by earlymoderntexts.com