Secondly, neither can our complex ideas of modes, in reference to the essence of anything really existing, be false; because whatever complex ideas I have of any mode, it hath no reference to any pattern existing, and made by nature; it is not supposed to contain in it any other ideas than what it hath; nor to represent anything but such a complication of ideas as it does.  Thus, when I have the idea of such an action of a man who forbears to afford himself such meat, drink, and clothing, and other conveniences of life, as his riches and estate will be sufficient to supply and his station requires, I have no false idea; but such an one as represents an action, either as I find or imagine it, and so is capable of neither truth nor falsehood.  But when I give the name frugality or virtue to this action, then it may be called a false idea, if thereby it be supposed to agree with that idea to which, in propriety of speech, the name of frugality doth belong, or to be conformable to that law which is the standard of virtue and vice.

18.  Thirdly, Ideas of Substances may be false in reference to existing things.

Thirdly, our complex ideas of substances, being all referred to patterns in things themselves, may be false.  That they are all false, when looked upon as the representations of the unknown essences of things, is so evident that there needs nothing to be said of it.  I shall therefore pass over that chimerical supposition, and consider them as collections of simple ideas in the mind, taken from combinations of simple ideas existing together constantly in things, of which patterns they are the supposed copies; and in this reference of them to the existence of things, they are false ideas:—­(1) When they put together simple ideas, which in the real existence of things have no union; as when to the shape and size that exist together in a horse, is joined in the same complex idea the power of barking like a dog:  which three ideas, however put together into one in the mind, were never united in nature; and this, therefore, may be called a false idea of a horse. (2) Ideas of substances are, in this respect, also false, when, from any collection of simple ideas that do always exist together, there is separated, by a direct negation, any other simple idea which is constantly joined with them.  Thus, if to extension, solidity, fusibility, the peculiar weightiness, and yellow colour of gold, any one join in his thoughts the negation of a greater degree of fixedness than is in lead or copper, he may be said to have a false complex idea, as well as when he joins to those other simple ones the idea of perfect absolute fixedness.  For either way, the complex idea of gold being made up of such simple ones as have no union in nature, may be termed false.  But, if he leaves out of this his complex idea that of fixedness quite, without either actually joining to or separating it from the rest in his mind, it is, I think, to be looked on as an inadequate and imperfect idea, rather than a false one; since, though it contains not all the simple ideas that are united in nature, yet it puts none together but what do really exist together.