n
occurs in things apparently the same, we know that they are really not
the same, but different.

Good.

For example, I said, can the same thing be at rest and in motion at the
same time in the same part?

Impossible.

Still, I said, let us have a more precise statement of terms, lest we
should hereafter fall out by the way. Imagine the case of a man who is
standing and also moving his hands and his head, and suppose a person
to say that one and the same person is in motion and at rest at the
same moment-to such a mode of speech we should object, and should
rather say that one part of him is in motion while another is at rest.

Very true.

And suppose the objector to refine still further, and to draw the nice
distinction that not only parts of tops, but whole tops, when they spin
round with their pegs fixed on the spot, are at rest and in motion at
the same time (and he may say the same of anything which revolves in
the same spot), his objection would not be admitted by us, because in
such cases things are not at rest and in motion in the same parts of
themselves; we should rather say that they have both an axis and a
circumference, and that the axis stands still, for there is no
deviation from the perpendicular; and that the circumference goes
round. But if, while revolving, the axis inclines either to the right
or left, forwards or backwards, then in no point of view can they be at
rest.

That is the correct mode of describing them, he replied.

Then none of these objections will confuse us, or incline us to believe
that the same thing at the same time, in the same part or in relation
to the same thing, can act or be acted upon in contrary ways.

Certainly not, according to my way of thinking.

Yet, I said, that we may not be compelled to examine all such
objections, and prove at length that they are untrue, let us assume
their absurdity, and go forward on the understanding that hereafter, if
this assumption turn out to be untrue, all the consequences which
follow shall be withdrawn.

Yes, he said, that will be the best way.

Well, I said, would you not allow that assent and dissent, desire and
aversion, attraction and repulsion, are all of them opposites, whether
they are regarded as active or passive (for that makes no difference in
the fact of their opposition)?

Yes, he said, they are opposites.

Well, I said, and hunger and thirst, and the desires in general, and
again willing and wishing,-