the whole bodies, they might be said to be analogous in the original mathematical sense of that word. But as this restrained sense is not applicable to things, as they really exist, another of a more enlarged and practical nature has been adopted, which may be thus defined. Analogy is that resemblance, and in some cases sameness, of the parts, properties, functions, uses, &c. any or all, of A to B, whereby our knowledge, concerning A, and the language expressing this knowledge, may be applied in the whole, or in part, to B, without any sensible, or, at least, any important practical error. Now analogies, in this sense of the word, some more exact and extensive, some less so, present themselves to us every where in natural and artificial things; and thus whole groups of figurative phrases, which seem at first only to answer the purposes of convenience in affording names for new objects, and of pleasing the fancy in the way to be hereafter mentioned, pass into analogical reasoning, and become a guide in the search after truth, and an evidence for it in some degree. I will here set down some instances of analogies of various degrees and kinds.
The bodies of men, women, and children, are highly analogous to each other. This holds equally in respect of every other species of animals; also of the several corresponding parts of animals of the same species, as their flesh, blood, bones, fat, &c. and their properties. Here the words applied to the several analogous things are used in a sense equally literal in respect of all. And the analogy is in most cases so close, as rather to be esteemed a coincidence, or sameness.
In comparing animals of different kinds the analogy grows perpetually less and less, as we take in a greater compass; and consequently our language more and more harsh, when considered as literal, whilst yet it cannot well be figurative in some things, and literal in others; so that new words are generally assigned to those parts which do not sufficiently resemble the corresponding ones. Thus the fore-legs of men and fowls, as we might call them in a harsh, literal, or a highly figurative way, are termed hands and wings respectively. However, in some cases, the same word is used, and considered as a figure; as when the cries of birds and beasts are termed their language. We may also observe, that every part in every animal may, from its resemblance in shape and use to the corresponding parts in several other animals, have a just right to a name, which shall be common to it and them.
What has been said of animals of the same and different kinds holds equally in respect of vegetables. Those of the same kind have the same names applied to the corresponding parts in a literal sense. Those of different kinds have many names common to all used in a literal sense, some new ones peculiar to certain kinds, and some that may be considered as so harsh in a literal sense, that we may rather call them figurative terms.