It is the special purpose of this book to set forth in a clear and rational manner the logic of vegetarianism. To the ethical, the scientific, and the economic aspects of the system much attention has already been given by well-accredited writers, but there has not as yet been any organised effort to present the _logical_ view—that is, the dialectical scope of the arguments, offensive and defensive, on which the case for vegetarianism is founded. I am aware that mere logic is not in itself a matter of first-rate importance, and that a great humane principal, based on true natural instinct, will in the long-run have fulfilment, whatever wordy battles may rage around it for a time; nevertheless, there is no better method of hastening that result than to set the issues before the public in a plain and unmistakable light. I wish, therefore, in this work, to show what vegetarianism is, and (a scarcely less essential point) what vegetarianism is _not_. For though, owing to the propaganda carried on for the last fifty years, there has been an increasing talk of vegetarianism, and a considerable discussion of its doctrines, there are still very numerous misunderstandings of its real aims and meaning. In this, as in other phases of the great progressive movement of which vegetarianism is a part, to give expression to a new idea is to excite a host of blind and angry prejudices. The champions of the old are too disdainful to take counsel with the champions of the new; hence they commonly attribute to them designs quite different from those which they really entertain, and unconsciously set up a straw man for the pleasure of pummelling him with criticism. Devoid always of a sense of sympathy, and mostly of a sense of humour, they absurdly exaggerate the least vital points in their adversaries' reasoning, while they often fail to note what is the very core of the controversy. It is therefore of great concern to vegetarianism that its case should be so stated as to preclude all possibility of doubt as to the real issues involved. If agreement is beyond our reach, let us at least ascertain the precise point of our disagreement.