Metaphysical Thoughts: Part 1, Chapter 5.
Concerning Opposition, Order, etc.
Because we compare objects one with another, there are certain
notions that arise, which, however apart from the
things themselves are only modes of thought. This is very evident,
since, when we attempt to consider them as
objects apart from forms of thought we hold the one for the
other and render clear concepts obscure. Such notions
are the following, viz., Opposition, Order, Relation, Diversity,
Connection, Conjunction, and other similar ideas.
These, I say, are perceived by us with sufficient clearness
provided we do not conceive of them as something in the essence
of things, but only as modes of thought by which we can more
easily retain these objects in memory and imagine
them. Therefore, I do not think it necessary to speak
further of this but pass to those terms commonly called transcendental.