17. Words and species.
I have mentioned this here, because I think we cannot be too cautious that words and
species, in the ordinary notions which we have been used to of them, impose not on us. For I am apt to think
therein lies one great obstacle to our clear and distinct knowledge, especially in reference to substances: and from
thence has risen a great part of the difficulties about truth and certainty. Would we accustom ourselves to separate
our contemplations and reasonings from words, we might in a great measure remedy this inconvenience within
our own thoughts: but yet it would still disturb us in our discourse with others, as long as we retained the opinion,
that species and their essences were anything else but our abstract ideas (such as they are) with names annexed to
them, to be the signs of them.
