eal 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 discourses 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
squaring of a circle, conic sections, or any other part of mathematics,
concern not the existence of any of those figures: 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 virtues 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 BOOK IV. 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 notions will there be of justice and
temperance? What confusion of virtues and vices, if every one may make
what ideas of them he pleases? No confusion or disorder in the things
themselves, nor the reasonings about them; no more than (in mathematics)
there would be a disturbance in the demonstration, or a change in the
properties of figures, a