13. Only particular propositions concerning concrete existences are knowable.
By which it appears that there are
two sorts of propositions:--(1) There is one sort of propositions concerning the existence of anything answerable
to such an idea: as having the idea of an elephant, phoenix, motion, or an angel, in my mind, the first and natural
inquiry is, Whether such a thing does anywhere exist? And this knowledge is only of particulars. No existence of
anything without us, but only of God, can certainly be known further than our senses inform us. (2) There is
another sort of propositions, wherein is expressed the agreement or disagreement of our abstract ideas, and their
dependence on one another. Such propositions may be universal and certain. So, having the idea of God and
myself, of fear and obedience, I cannot but be sure that God is to be feared and obeyed by me: and this
proposition will be certain, concerning man in general, if I have made an abstract idea of such a species, whereof I
am one particular. But yet this proposition, how certain soever, that "men ought to fear and obey God" proves not
to me the existence of men in the world; but will be true of all such creatures, whenever they do exist: which
certainty of such general propositions depends on the agreement or disagreement to be discovered in those
abstract ideas.