9. General propositions concerning substances are often trifling.
We having little or no knowledge of what
combinations there be of simple ideas existing together in substances, but by our senses, we cannot make any
universal certain propositions concerning them, any further than our nominal essences lead us. Which being to a
very few and inconsiderable truths, in respect of those which depend on their real constitutions, the general
propositions that are made about substances, if they are certain, are for the most part but trifling; and if they are
instructive, are uncertain, and such as we can have no knowledge of their real truth, how much soever constant
observation and analogy may assist our judgment in guessing. Hence it comes to pass, that one may often meet
with very clear and coherent discourses, that amount yet to nothing. For it is plain that names of substantial
beings, as well as others, as far as they have relative significations affixed to them, may, with great truth, be
joined negatively and affirmatively in propositions, as their relative definitions make them fit to be so joined; and
propositions consisting of such terms, may, with the same clearness, be deduced one from another, as those that
convey the most real truths: and all this without any knowledge of the nature or reality of things existing without
us. By this method one may make demonstrations and undoubted propositions in words, and yet thereby advance
not one jot in the knowledge of the truth of things: v.g. he that having learnt these following words, with their
ordinary mutual relative acceptations annexed to them: v.g. substance, man, animal, form, soul, vegetative,
sensitive, rational, may make several undoubted propositions about the soul, without knowing at all what the soul
really is: and of this sort, a man may find an infinite number of propositions, reasonings, and conclusions, in
books of metaphysics, school-divinity, and some sort of natural philosophy: and, after all, know as little of God,
spirits, or bodies, as he did before he set out.
