require demonstration, and demand certainty, where probability only is
to be had, and which is sufficient to govern all our concernments.
If we will disbelieve everything, because we cannot certainly know all
things, we shall do muchwhat as wisely as he who would not use his
legs, but sit still and perish, because he had no wings to fly.

  6. Knowledge of our capacity a cure of scepticism and idleness. When
we know our own strength, we shall the better know what to undertake
with hopes of success; and when we have well surveyed the powers of
our own minds, and made some estimate what we may expect from them, we
shall not be inclined either to sit still, and not set our thoughts on
work at all, in despair of knowing anything; nor on the other side,
question everything, 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, though he cannot with it fathom all the depths
of the ocean. It is well he knows that it 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.

  7. Occasion of this essay. This was that which gave the first rise
to this Essay concerning the understanding. For 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; as if all that boundless extent were the natural and
undoubted possession of our understandings, wherein there was
nothing exempt from its decisions, or that escaped its
comprehension. Thus men, extending their inquiries beyond their
capacities, and letting their thoughts wander into those depths
where they can find no sure footing, it is no wonder that they raise
questions and multiply disputes, which, never coming to any clear
resolution, are proper only to continue and increase their doubts, and
to confirm them at last in perfect scepticism. Whereas, were the
capacities of our understandings well considered, the extent of our
knowledge once discovered, and the horizon found which sets the bounds
between the enlightened and dark parts of things; between what is
and what is not comprehensible by us, men would perhaps with less
scruple acquiesce in the avowed ignorance of the one, and employ their
thoughts and discourse with more advantage and satisfaction in the
other.

  8. What "Idea" stands for. Thus much I thought necessary to say
concerning the occasion of this Inquiry into human Understanding. But,
before I proceed on to what I have thought on this subject, 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 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.

                                BOOK I

               Neither Principles nor Ideas Are Innate

                              Chapter I

                   No Innate Speculative Principles

  1. The way shown how we come by any knowledge, sufficient to prove
it not innate. It is an established opinion amongst some men, that
there are in the understanding certain innate principles; some primary
notions, koinai ennoiai, characters, as it were 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, barely by the use of their natural faculties, may attain to
all the knowledge they have, without the help of any innate
impressions; and may arrive at certainty, without any such original
notions or principles. For I imagine any one will easily grant that it
would be impertinent to suppose the ideas of colours innate in a
creature to whom God hath given sight, and a power to receive them
by the eyes from external objects: and no less unreasonable would it
be to attribute several truths to the impressions of nature, and
innate characters, when we may observe in ourselves faculties fit to
attain as easy and certain knowledge of them as if they were
originally imprinted on the mind.

  But because a man is not permitted without censure to follow his own
thoughts in the search of truth, when they lead him ever so little out
of the common road, I shall set down the reasons that made me doubt of
the truth of that opinion, as an excuse for my mistake, if I be in
one; which I leave to be considered by those who, with me, dispose
themselves to embrace truth wherever they find it.