Philosiphy

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are. There is another extent of it, in respect of univer-

sality, which will also deserve to be considered; and in

this regard, our knowledge follows the nature of our

ideas. If the ideas are abstract, whose agreement or dis-

agreement we perceive, our knowledge is universal. For

what is known of such general ideas, will be true of

every particular thing in whom that essence, i.e. that

abstract idea, is to be found: and what is once known of

such ideas, will be perpetually and for ever true. So that

as to all general knowledge we must search and find it

only in our minds; and it is only the examining of our

own ideas that furnisheth us with that. Truths belong-

ing to essences of things (that is, to abstract ideas) are

eternal; and are to be found out by the contemplation

only of those essences: as the existence of things is to

be known only from experience. But having more to say

of this in the chapters where I shall speak of general and

real knowledge, this may here suffice as to the univer-

sality of our knowledge in general.

Chapter IV Of the Reality of Knowledge

1. Objection. “Knowledge placed in our ideas may be all

unreal or chimerical.” I doubt not but my reader, by

this time, may be apt to think that I have been all this

while only building a castle in the air; and be ready to

say to me:

“To what purpose all this stir? Knowledge, say you, is

only the perception of the agreement or disagreement

of our own ideas: but who knows what those ideas may

be? Is there anything so extravagant as the imagina-

tions of men’s brains? Where is the head that has no

chimeras in it? Or if there be a sober and a wise man,

what difference will there be, by your rules, between

his knowledge and that of the most extravagant fancy

in the world? They both have their ideas, and perceive

their agreement and disagreement one with another. If

there be any difference between them, the advantage

will be on the warm-headed man’s side, as having the

more ideas, and the more lively. And so, by your rules,

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he will be the more knowing. If it be true, that all knowl-

edge lies only in the perception of the agreement or

disagreement of our own ideas, the visions of an enthu-

siast and the reasonings of a sober man will be equally

certain. It is no matter how things are: so a man ob-

serve but the agreement of his own imaginations, and

talk conformably, it is all truth, all certainty. Such castles

in the air will be as strongholds of truth, as the demon-

strations of Euclid. That an harpy is not a centaur is by

this way as certain knowledge, and as much a truth, as

that a square is not a circle.”

“But of what use is all this fine knowledge of men’s

own imaginations, to a man that inquires after the real-

ity of things? It matters not what men’s fancies are, it is

the knowledge of things that is only to be prized: it is

this alone gives a value to our reasonings, and preference

to one man’s knowledge over another’s, that it is of things

as they really are, and not of dreams and fancies.”

2. Answer: “Not so, where ideas agree with things.” To

which I answer, That if our knowledge of our ideas ter-

minate in them, and reach no further, where there is

something further intended, our most serious thoughts

will be of little more use than the reveries of a crazy

brain; and the truths built thereon of no more weight

than the discourses of a man who sees things clearly in

a dream, and with great assurance utters them. But I

hope, before I have done, to make it evident, that this

way of certainty, by the knowledge of our own ideas,

goes a little further than bare imagination: and I believe

it will appear that all the certainty of general truths a

man has lies in nothing else.

3. But what shall be the criterion of this agreement? It

is evident the mind knows not things immediately, but

only by the intervention of the ideas it has of them. Our

knowledge, therefore is real only so far as there is a

conformity between our ideas and the reality of things.

But what shall be here the criterion? How shall the

mind, when it perceives nothing but its own ideas, know

that they agree with things themselves? This, though it

seems not to want difficulty, yet, I think, there be two

sorts of ideas that we may be assured agree with things.

4. As all simple ideas are really conformed to things.

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First, The first are simple ideas, which since the mind, as

has been shown, can by no means make to itself, must

necessarily be the product of things operating on the

mind, in a natural way, and producing therein those

perceptions which by the Wisdom and Will of our Maker

they are ordained and adapted to. From whence it fol-

lows, that simple ideas are not fictions of our fancies,

but the natural and regular productions of things with-

out us, really operating upon us; and so carry with them

all the conformity which is intended; or which our state

requires: for they represent to us things under those

appearances which they are fitted to produce in us:

whereby we are enabled to distinguish the sorts of par-

ticular substances, to discern the states they are in, and

so to take them for our necessities, and apply them to

our uses. Thus the idea of whiteness, or bitterness, as it

is in the mind, exactly answering that power which is in

any body to produce it there, has all the real conformity

it can or ought to have, with things without us. And

this conformity between our simple ideas and the exist-

ence of things, is sufficient for real knowledge.

5. All complex ideas, except ideas of substances, are

their own archetypes. Secondly, All our complex ideas,

except those of substances, being archetypes of the

mind’s own making, not intended to be the copies of

anything, nor referred to the existence of anything, as

to their originals, cannot want any conformity neces-

sary to real knowledge. For that which is not designed

to represent anything but itself, can never be capable of

a wrong representation, nor mislead us from the true

apprehension of anything, by its dislikeness to it: and

such, excepting those of substances, are all our complex

ideas. Which, as I have shown in another place, are com-

binations of ideas, which the mind, by its free choice,

puts together, without considering any connexion they

have in nature. And hence it is, that in all these sorts

the ideas themselves are considered as the archetypes,

and things no otherwise regarded, but as they are con-

formable to them. So that we cannot but be infallibly

certain, that all the knowledge we attain concerning

these ideas is real, and reaches things themselves. Be-

cause in all our thoughts, reasonings, and discourses of

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this kind, we intend things no further than as they are

conformable to our ideas. So that in these we cannot

miss of a certain and undoubted reality.

6. Hence the reality of mathematical knowledge. I doubt

not but it will be easily granted, that the knowledge we

have of mathematical truths is not only certain, but

real knowledge; and not the bare empty vision of vain,

insignificant chimeras of the brain: and yet, if we will

consider, we shall find that it is only of our own ideas.

The mathematician considers the truth and properties

belonging to a rectangle or circle only as they are in

idea in his own mind. For it is possible he never found

either of them existing mathematically, i.e. precisely true,

in his life. But yet the knowledge he has of any truths

or properties belonging to a circle, or any other math-

ematical figure, are nevertheless true and certain, even

of real things existing: because real things are no fur-

ther concerned, nor intended to be meant by any such

propositions, than as things really agree to those arche-

types in his mind. Is it true of the idea of a triangle,

that its three angles are equal to two right ones? It is

true also of a triangle, wherever it really exists. What-

ever other figure exists, that it is not exactly answer-

able to that idea of a triangle in his mind, is not at all

concerned in that proposition. And therefore he is cer-

tain all his knowledge concerning such ideas is real knowl-

edge: because, intending things no further than they

agree with those his ideas, he is sure what he knows

concerning those figures, when they have barely an ideal

existence in his mind, will hold true of them also when

they have a real existence in matter: his consideration

being barely of those figures, which are the same wher-

ever or however they exist.

7. And of moral. And hence it follows that moral knowl-

edge is as capable of real certainty as mathematics. For

certainty being but the perception of the agreement or

disagreement of our ideas, and demonstration nothing

but the perception of such agreement, by the interven-

tion of other ideas or mediums; our moral ideas, as well

as mathematical, being archetypes themselves, and so

adequate and complete ideas; all the agreement or dis-

agreement which we shall find in them will produce real

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knowledge, as well as in mathematical figures.

8. Existence not required to make abstract knowledge

real. For the attaining of knowledge and certainty, it is

requisite that we have determined ideas: and, to make

our knowledge real, it is requisite that the ideas answer

their archetypes. Nor let it be wondered, that I place

the certainty of our knowledge in the consideration of

our ideas, with so little care and regard (as it may seem)

to the real existence of things: since most of those dis-

courses which take up the thoughts and engage the

disputes of those who pretend to make it their business

to inquire after truth and certainty, will, I presume,

upon examination, be found to be general propositions,

and notions in which existence is not at all concerned.

All the discourses of the mathematicians about the squar-

ing of a circle, conic sections, or any other part of math-

ematics, concern not the existence of any of those fig-

ures: but their demonstrations, which depend on their

ideas, are the same, whether there be any square or

circle existing in the world or no. In the same manner,

the truth and certainty of moral discourses abstracts

from the lives of men, and the existence of those vir-

tues in the world whereof they treat: nor are Tully’s

Offices less true, because there is nobody in the world

that exactly practises his rules, and lives up to that

pattern of a virtuous man which he has given us, and

which existed nowhere when he writ but in idea. If it be

true in speculation, i.e. in idea, that murder deserves

death, it will also be true in reality of any action that

exists conformable to that idea of murder. As for other

actions, the truth of that proposition concerns them

not. And thus it is of all other species of things, which

have no other essences but those ideas which are in the

minds of men.

9. Nor will it be less true or certain, because moral

ideas are of our own making and naming. But it will

here be said, that if moral knowledge be placed in the

contemplation of our own moral ideas, and those, as

other modes, be of our own making, What strange no-

tions will there be of justice and temperance? What con-

fusion of virtues and vice, if every one may make what

ideas of them he pleases? No confusion or disorder in

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the things themselves, nor the reasonings about them;

no more than (in mathematics) there would be a distur-

bance in the demonstration, or a change in the proper-

ties of figures, and their relations one to another, if a

man should make a triangle with four corners, or a tra-

pezium with four right angles: that is, in plain English,

change the names of the figures, and call that by one

name, which mathematicians call ordinarily by another.

For, let a man make to himself the idea of a figure with

three angles, whereof one is a right one, and call it, if he

please, equilaterum or trapezium, or anything else; the

properties of, and demonstrations about that idea will

be the same as if he called it a rectangular triangle. I

confess the change of the name, by the impropriety of

speech, will at first disturb him who knows not what

idea it stands for: but as soon as the figure is drawn, the

consequences and demonstrations are plain and clear.

Just the same is it in moral knowledge: let a man have

the idea of taking from others, without their consent,

what their honest industry has possessed them of, and

call this justice if he please. He that takes the name here

without the idea put to it will be mistaken, by joining

another idea of his own to that name: but strip the idea

of that name, or take it such as it is in the speaker’s

mind, and the same things will agree to it, as if you

called it injustice. Indeed, wrong names in moral dis-

courses breed usually more disorder, because they are

not so easily rectified as in mathematics, where the fig-

ure, once drawn and seen, makes the name useless and

of no force. For what need of a sign, when the thing

signified is present and in view? But in moral names,

that cannot be so easily and shortly done, because of

the many decompositions that go to the making up the

complex ideas of those modes. But yet for all this, the

miscalling of any of those ideas, contrary to the usual

signification of the words of that language, hinders not

but that we may have certain and demonstrative knowl-

edge of their several agreements and disagreements, if

we will carefully, as in mathematics, keep to the same

precise ideas, and trace them in their several relations

one to another, without being led away by their names.

If we but separate the idea under consideration from

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the sign that stands for it, our knowledge goes equally

on in the discovery of real truth and certainty, what-

ever sounds we make use of.

10. Misnaming disturbs not the certainty of the knowl-

edge. One thing more we are to take notice of, That

where God or any other law-maker, hath defined any

moral names, there they have made the essence of that

species to which that name belongs; and there it is not

safe to apply or use them otherwise: but in other cases

it is bare impropriety of speech to apply them contrary

to the common usage of the country. But yet even this

too disturbs not the certainty of that knowledge, which

is still to be had by a due contemplation and comparing

of those even nicknamed ideas.

11. Our complex ideas of substances have their arche-

types without us; and here knowledge comes short.

Thirdly, There is another sort of complex ideas, which,

being referred to archetypes without us, may differ from

them, and so our knowledge about them may come short

of being real. Such are our ideas of substances, which,

consisting of a collection of simple ideas, supposed taken

from the works of nature, may yet vary from them; by

having more or different ideas united in them than are

to be found united in the things themselves. From

whence it comes to pass, that they may, and often do,

fail of being exactly conformable to things themselves.

12. So far as our complex ideas agree with those arche-

types without us, so far our knowledge concerning sub-

stances is real. I say, then, that to have ideas of sub-

stances which, by being conformable to things, may

afford us real knowledge, it is not enough, as in modes,

to put together such ideas as have no inconsistence,

though they did never before so exist: v.g. the ideas of

sacrilege or perjury, &c., were as real and true ideas

before, as after the existence of any such fact. But our

ideas of substances, being supposed copies, and referred

to archetypes without us, must still be taken from some-

thing that does or has existed: they must not consist of

ideas put together at the pleasure of our thoughts, with-

out any real pattern they were taken from, though we

can perceive no inconsistence in such a combination.

The reason whereof is, because we, knowing not what

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real constitution it is of substances whereon our simple

ideas depend, and which really is the cause of the strict

union of some of them one with another, and the exclu-

sion of others there are very few of them that we can be

sure are or are not inconsistent in nature, any further

than experience and sensible observation reach. Herein,

therefore, is founded the reality of our knowledge con-

cerning substances—That all our complex ideas of them

must be such, and such only, as are made up of such

simple ones as have been discovered to co-exist in na-

ture. And our ideas being thus true, though not per-

haps very exact copies, are yet the subjects of real (as

far as we have any) knowledge of them. Which (as has

been already shown) will not be found to reach very far:

but so far as it does, it will still be real knowledge. What-

ever ideas we have, the agreement we find they have

with others will still be knowledge. If those ideas be

abstract, it will be general knowledge. But to make it

real concerning substances, the ideas must be taken from

the real existence of things. Whatever simple ideas have

been found to co-exist in any substance, these we may

with confidence join together again, and so make ab-

stract ideas of substances. For whatever have once had

an union in nature, may be united again.

13. In our inquiries about substances, we must con-

sider ideas, and not confine our thoughts to names or

species supposed set out by names. This, if we rightly

consider, and confine not our thoughts and abstract

ideas to names, as if there were, or could be no other

sorts of things than what known names had already

determined, and, as it were, set out, we should think of

things with greater freedom and less confusion than

perhaps we do. It would possibly be thought a bold para-

dox, if not a very dangerous falsehood, if I should say

that some changelings, who have lived forty years to-

gether, without any appearance of reason, are some-

thing between a man and a beast: which prejudice is

founded upon nothing else but a false supposition, that

these two names, man and beast, stand for distinct spe-

cies so set out by real essences, that there can come no

other species between them: whereas if we will abstract

from those names, and the supposition of such specific

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essences made by nature, wherein all things of the same

denominations did exactly and equally partake; if we

would not fancy that there were a certain number of

these essences, wherein all things, as in moulds, were

cast and formed; we should find that the idea of the

shape, motion, and life of a man without reason, is as

much a distinct idea, and makes as much a distinct sort

of things from man and beast, as the idea of the shape

of an ass with reason would be different from either

that of man or beast, and be a species of an animal

between, or distinct from both.

14. Objection against a changeling being something

between a man and beast, answered. Here everybody

will be ready to ask, If changelings may be supposed

something between man and beast, pray what are they?

I answer, changelings; which is as good a word to sig-

nify something different from the signification of man

or beast, as the names man and beast are to have signi-

fications different one from the other. This, well consid-

ered, would resolve this matter, and show my meaning

without any more ado. But I am not so unacquainted

with the zeal of some men, which enables them to spin

consequences, and to see religion threatened, whenever

any one ventures to quit their forms of speaking, as not

to foresee what names such a proposition as this is like

to be charged with: and without doubt it will be asked,

If changelings are something between man and beast,

what will become of them in the other world? To which

I answer, I. It concerns me not to know or inquire. To

their own master they stand or fall. It will make their

state neither better nor worse, whether we determine

anything of it or no. They are in the hands of a faithful

Creator and a bountiful Father, who disposes not of his

creatures according to our narrow thoughts or opin-

ions, nor distinguishes them according to names and

species of our contrivance. And we that know so little

of this present world we are in, may, I think, content

ourselves without being peremptory in defining the dif-

ferent states which creatures shall come into when they

go off this stage. It may suffice us, that He hath made

known to all those who are capable of instruction, dis-

coursing, and reasoning, that they shall come to an

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account, and receive according to what they have done

in this body.

15. What will become of changelings in a future state?

But, Secondly, I answer, The force of these men’s ques-

tion (viz. Will you deprive changelings of a future state?)

is founded on one of these two suppositions, which are

both false. The first is, That all things that have the

outward shape and appearance of a man must necessar-

ily be designed to an immortal future being after this

life: or, secondly, That whatever is of human birth must

be so. Take away these imaginations, and such ques-

tions will be groundless and ridiculous. I desire then

those who think there is no more but an accidental

difference between themselves and changelings, the es-

sence in both being exactly the same, to consider,

whether they can imagine immortality annexed to any

outward shape of the body; the very proposing it is, I

suppose, enough to make them disown it. No one yet,

that ever I heard of, how much soever immersed in mat-

ter, allowed that excellency to any figure of the gross

sensible outward parts, as to affirm eternal life due to

it, or a necessary consequence of it; or that any mass of

matter should, after its dissolution here, be again re-

stored hereafter to an everlasting state of sense, percep-

tion, and knowledge, only because it was moulded into

this or that figure, and had such a particular frame of

its visible parts. Such an opinion as this, placing immor-

tality in a certain superficial figure, turns out of doors

all consideration of soul or spirit; upon whose account

alone some corporeal beings have hitherto been con-

cluded immortal, and others not. This is to attribute

more to the outside than inside of things; and to place

the excellency of a man more in the external shape of

his body, than internal perfections of his soul: which is

but little better than to annex the great and inesti-

mable advantage of immortality and life everlasting,

which he has above other material beings, to annex it, I

say, to the cut of his beard, or the fashion of his coat.

For this or that outward mark of our bodies no more

carries with it the hope of an eternal duration, than the

fashion of a man’s suit gives him reasonable grounds to

imagine it will never wear out, or that it will make him

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immortal. It will perhaps be said, that nobody thinks

that the shape makes anything immortal, but it is the

shape is the sign of a rational soul within, which is

immortal. I wonder who made it the sign of any such

thing: for barely saying it, will not make it so. It would

require some proofs to persuade one of it. No figure that

I know speaks any such language. For it may as ratio-

nally be concluded, that the dead body of a man, wherein

there is to be found no more appearance or action of life

than there is in a statue, has yet nevertheless a living

soul in it, because of its shape; as that there is a ratio-

nal soul in a changeling, because he has the outside of a

rational creature, when his actions carry far less marks

of reason with them, in the whole course of his life,

than what are to be found in many a beast.

16. Monsters. But it is the issue of rational parents,

and must therefore be concluded to have a rational soul.

I know not by what logic you must so conclude. I am

sure this is a conclusion that men nowhere allow of. For

if they did, they would not make bold, as everywhere

they do, to destroy ill-formed and mis-shaped produc-

tions. Ay, but these are monsters. Let them be so: what

will your drivelling, unintelligent, intractable change-

ling be? Shall a defect in the body make a monster; a

defect in the mind (the far more noble, and, in the com-

mon phrase, the far more essential part) not? Shall the

want of a nose, or a neck, make a monster, and put such

issue out of the rank of men; the want of reason and

understanding, not? This is to bring all back again to

what was exploded just now: this is to place all in the

shape, and to take the measure of a man only by his

outside. To show that according to the ordinary way of

reasoning in this matter, people do lay the whole stress

on the figure, and resolve the whole essence of the spe-

cies of man (as they make it) into the outward shape,

how unreasonable soever it be, and how much soever

they disown it, we need but trace their thoughts and

practice a little further, and then it will plainly appear.

The well-shaped changeling is a man, has a rational soul,

though it appear not: this is past doubt, say you: make

the ears a little longer, and more pointed, and the nose

a little flatter than ordinary, and then you begin to

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boggle: make the face yet narrower, flatter, and longer,

and then you are at a stand: add still more and more of

the likeness of a brute to it, and let the head be per-

fectly that of some other animal, then presently it is a

monster; and it is demonstration with you that it hath

no rational soul, and must be destroyed. Where now (I

ask) shall be the just measure; which the utmost bounds

of that shape, that carries with it a rational soul? For,

since there have been human foetuses produced, half

beast and half man; and others three parts one, and one

part the other; and so it is possible they may be in all

the variety of approaches to the one or the other shape,

and may have several degrees of mixture of the likeness

of a man, or a brute;—I would gladly know what are

those precise lineaments, which, according to this hy-

pothesis, are or are not capable of a rational soul to be

joined to them. What sort of outside is the certain sign

that there is or is not such an inhabitant within? For

till that be done, we talk at random of man: and shall

always, I fear, do so, as long as we give ourselves up to

certain sounds, and the imaginations of settled and fixed

species in nature, we know not what. But, after all, I

desire it may be considered, that those who think they

have answered the difficulty, by telling us, that a mis-

shaped foetus is a monster, run into the same fault they

are arguing against; by constituting a species between

man and beast. For what else, I pray, is their monster in

the case, (if the word monster signifies anything at all,)

but something neither man nor beast, but partaking

somewhat of either? And just so is the changeling be-

fore mentioned. So necessary is it to quit the common

notion of species and essences, if we will truly look into

the nature of things, and examine them by what our

faculties can discover in them as they exist, and not by

groundless fancies that have been taken up about them.

17. Words and species. I have mentioned this here, be-

cause I think we cannot be too cautious that words and

species, in the ordinary notions which we have been

used to of them, impose not on us. For I am apt to think

therein lies one great obstacle to our clear and distinct

knowledge, especially in reference to substances: and

from thence has risen a great part of the difficulties

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about truth and certainty. Would we accustom ourselves

to separate our contemplations and reasonings from

words, we might in a great measure remedy this incon-

venience within our own thoughts: but yet it would

still disturb us in our discourse with others, as long as

we retained the opinion, that species and their essences

were anything else but our abstract ideas (such as they

are) with names annexed to them, to be the signs of

them.

18. Recapitulation. Wherever we perceive the agree-

ment or disagreement of any of our ideas, there is cer-

tain knowledge: and wherever we are sure those ideas

agree with the reality of things, there is certain real

knowledge. Of which agreement of our ideas with the

reality of things, having here given the marks, I think,

I have shown wherein it is that certainty, real certainty,

consists. Which, whatever it was to others, was, I con-

fess, to me heretofore, one of those desiderata which I

found great want of.

Chapter V Of Truth in General

1. What truth is. What is truth? was an inquiry many

ages since; and it being that which all mankind either

do, or pretend to search after, it cannot but be worth

our while carefully to examine wherein it consists, and

so acquaint ourselves with the nature of it, as to ob-

serve how the mind distinguishes it from falsehood.

2. A right joining or separating of signs, i.e. either

ideas or words. Truth, then, seems to me, in the proper

import of the word, to signify nothing but the joining

or separating of Signs, as the Things signified by them

do agree or disagree one with another. The joining or

separating of signs here meant, is what by another name

we call proposition. So that truth properly belongs only

to propositions: whereof there are two sorts, viz. men-

tal and verbal; as there are two sorts of signs commonly

made use of, viz. ideas and words.

3. Which make mental or verbal propositions. To form a

clear notion of truth, it is very necessary to consider