will equally suit any other that is exactly like it. It is not intended to recommend the disuse of the words "same," "identical," &c. in this transferred sense; which, if it were desirable would be utterly impracticable; but merely a steady attention to the ambiguity thus introduced, and watchfulness against the errors thence arising.* The difficulties and perplexities which have involved the questions respecting personal identity, among others, may be traced principally to the neglect of this caution. But a full consideration * It is with words as with money. Those who know the value of it best, are not therefore the least liberal. We may lend readily and largely; and though this be done. quietly and without ostentation, there is no harm in keeping an exact account in our private memorandum-book of the sums, the persons, and the occasions on which they were lent. It may be, we shall want them again for our own use; or they may be employed by the borrower for a wrong purpose; or they may have been so long in his possession that he begins to look upon them as his own. In either of which cases it is allowable, and even right, to call them in. "Logic Vindicated." Oxford, 1809. I mean that many writers have sought an explanation of the primary sense of identity (viz. personal) by looking to the secondary. Any grown man, e. g. is, in the primary sense, the same person he was when a child: this sameness is, I conceive, a simple notion, which it is vain to attempt explaining by any other more simple; but when philosophers seek to gain a clearer notion of it by looking to the cases in which sameness is predicated in another sense, viz. similarity, such as exists between several individuals of that question would be unsuitable to the subject of this work. denoted by a common name, (as when we say that there are growing on Lebanon some of the same trees with which the Temple was built, meaning cedars of that species) this is surely as idle as if we were to attempt explaining the primary sense, e.g. of "rage," as it exists in the human mind, by directing our attention to the "rage" of the sea. Whatever personal identity does consist in, it is plain that it has nothing to do with similarity; since every one would be ready to say, "When I WAS a child, I thought as a child, I spake as a child,-I understood as a child; but when I became a man, I put away childish things." IT has appeared to me desirable to illustrate the importance of attending to the ambiguity of terms, by a greater number of instances than could have been conveniently either inserted in the context or introduced in a note, without too much interrupting the course of the discussion of Fallacies. I have purposely selected instances from various subjects, and some from the most important; being convinced that the disregard and contempt with which logical studies are |