how far their discoveries were
advanced, or what was wanting in their own, or the general stock of
knowledge. Had men, in the discoveries of the material, done as they
have in those of the intellectual world, involved all in the obscurity
of uncertain and doubtful ways of talking, volumes writ of navigation
and voyages, theories and stories of zones and tides, multiplied and
disputed; nay, ships built, and fleets sent out, would never have taught
us the way beyond the line; and the Antipodes would be still as much
unknown, as when it was declared heresy to hold there were any. But
having spoken sufficiently of words, and the ill or careless use that is
commonly made of them, I shall not say anything more of it here.

31. Extent of Human Knowledge in respect to its Universality.

Hitherto we have examined the extent of our knowledge, in respect of
the several sorts of beings that are. There is another extent of it, in
respect of UNIVERSALITY, 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 disagreement 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 belonging 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 universality 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
imaginations of men's brains? W