How much names taken for things are apt to mislead the understanding, the attentive reading of philosophical writers would abundantly discover; and that perhaps in words little suspected of any such misuse.  I shall instance in one only, and that a very familiar one.  How many intricate disputes have there been about matter, as if there were some such thing really in nature, distinct from body; as it is evident the word matter stands for an idea distinct from the idea of body?  For if the ideas these two terms stood for were precisely the same, they might indifferently in all places be put for one another.  But we see that though it be proper to say, There is one matter of all bodies, one cannot say, There is one body of all matters:  we familiarly say one body is bigger than another; but it sounds harsh (and I think is never used) to say one matter is bigger than another.  Whence comes this, then?  Viz. from hence:  that, though matter and body be not really distinct, but wherever there is the one there is the other; yet matter and body stand for two different conceptions, whereof the one is incomplete, and but a part of the other.  For body stands for a solid extended figured substance, whereof matter is but a partial and more confused conception; it seeming to me to be used for the substance and solidity of body, without taking in its extension and figure:  and therefore it is that, speaking of matter, we speak of it always as one, because in truth it expressly contains nothing but the idea of a solid substance, which is everywhere the same, everywhere uniform.  This being our idea of matter, we no more conceive or speak of different matters in the world than we do of different solidities; though we both conceive and speak of different bodies, because extension and figure are capable of variation.  But, since solidity cannot exist without extension and figure, the taking matter to be the name of something really existing under that precision, has no doubt produced those obscure and unintelligible discourses and disputes, which have filled the heads and books of philosophers concerning materia prima; which imperfection or abuse, how far it may concern a great many other general terms I leave to be considered.  This, I think, I may at least say, that we should have a great many fewer disputes in the world, if words were taken for what they are, the signs of our ideas only; and not for things themselves.  For, when we argue about matter, or any the like term, we truly argue only about the idea we express by that sound, whether that precise idea agree to anything really existing in nature or no.  And if men would tell what ideas they make their words stand for, there could not be half that obscurity or wrangling in the search or support of truth that there is.

16.  This makes Errors lasting.