SCIENCE. The word scientla, in real Latin, simply means know ledge, and we must attribute the subsequent application of the word to particular kinds of knowledge, to causes similar to those which have influenced the use of the equally general term MATHEMATICS. It does not appear that in the earlier parts of the middle ages science had any distinct meaning as opposed either to literature or to art. Almost at the earliest establishment of universities, the great preliminary branches of knowledge were separated from the rest under the name of liberal arts ; that is to say, the Trivium, containing grammar, logic, and rhetoric ; and the Qundrivium, containing arithmetic, geometry, astro nomy, and music. If theology, law, and medicine were called sciences, it was not in any distinctive sense, and we are inclined to think that ecientia must then have been rather a term subaltern to art, than opposed to it. We find Roger Bacon (` Op. Maj.; cap. xv.) speaking of the nine mathematical sciences, and the six great natural sciences, which contain under them many other sciences : and his contemporary Robert of Lincoln (` Tract. de Art. Lib:), after laying it down that the arts (not sciences), of which it is the office " operationes humans corrigendo ad perfectioncm duccre," are seven in number, proceeds to describe them without a single use of the word science. How the word grew it is not our business to inquire closely ; but by the middle of the 16th century the word science had begun to appear as denoting connected and demonstrated knowledge, in opposition to art, which signified digested rules of operation not connected with each other by deduction from common first principles. Thus Tartaglia, a writer on algebra (which was then, and most properly, called only an art ; ars magna. or ante maggiore), styles Euclid, in the preface to his edition of the Elements, " the sole guide to the mathematical sciences." By the middle of the 17th century, the term science was freely used in the sense which it has never since lost, namely, that in which it is opposed to literature. But the old distinction of science as opposed to art has still remained, though the two terms, in this sense, have been in great measure superseded by theory and practice ; but improperly, for the distinction between science and art is one thing, and that between theory and practice another. [TriEoass]
A science, as distinguished from an art, is a body of truths, the common first principles of which are supposed to be known and sepa rated, so that the individual truths, even though some or all may be clear in themselves, have a guarantee that they could have been dis covered and known, either with certainty or with such probability as the subject admits of, by other means than their own evidence. It is not necessary that these truths should have been discovered by a scientific process ; it is enough that they admit of such treatment subsequently. The telescope, for instance, may have been discovered accidentally; but it can now be demonstrated beforehand that such an instrument must produce the effect which it is known to produce, and the rules for its construction may be deduced from the simple funda mental properties of light. In the sense of the word above used, the number of perfect sciences is not so great as is commonly sup posed ; for many branches of knowledge which bear the name are not perfect sciences, such as medicine, zoology, and geology ; in all of these, large classifications have been made, many principles have been deduced which seem to be of universal application, and much has been done to make these known principles point out the direction of inquiry ; but it would be idle to say that either of them is a science in the sense in which astronomy is a science.
Science, as opposed to literature, means any branch of knowledge in which the affections of mind or matter are to be made the subject of reasoning, with a view to discover and apply first principles. The dis tinctions of mental and physical sciences, the subdivision of the former into ethical and psychological, &c., whatever terms may be employed, are real and useful. But as it is not the object here to classify human knowledge, but only to give a slight account of the mode of using a word, we may pass on to its common signification.