Principle

A fundamental truth; an

1. A fundamental truth; an elementary proposition; a settled rule of action or procedure. Compare Maxim. 2. In patent law, a fundamental truth, an original cause. These cannot be patented, as no one can claim in either of them an exclusive right. The processes used to extract, modify, and concentrate natural agencies, constitute the invention. The elements of the power exist; the invention is not in discovering them, but in applying them to useful objects. There is no authority for granting a patent for a "principle," an idea, or any other abstraction. The principle of a machine is "its mode of operation," or that peculiar combination of devices which distinguish it from other machines. The machine is not the principle or the idea. To make useful and patentable the discovery of a new principle, it must be applied to a practical purpose. The practical application to some useful purpose is the test of its value. When mechanical devices operate substantially in the same way, producing a similar result, they are considered the same in principle. See Patent, 2.

In the patent law^ the principle of a machine is the particular means of producing a given result by a mechanical contrivance. Parker v. Stiles, 5 Mc Lean, 44, 63; 8. c. 7 West. Law J. 168. The term does not mean a new mechanical power: none such have been discovered for centuries. That is a principle which applies, modifies, or combines mechanical powers to produce a certain result. Smith u. Pearce, 2 Mc Lean, 176. Where two machines or things are made to operate substantially in the same way, so as to produce the same result, they are considered the same in principle. Thus, where any of the mechanical powers, the lever, screw, wheel, &c., are used to accomplish certain purposes, the same powers being used, the fact that they are used in a somewhat different form to do the same thing will not constitute a difference in principle. Whether the mechanical instruments be larger or smaller, whether their action be horizontal or vertical, As to what constitutes the " principle " of a machine, see also Le Roy V. Tatham, 22 How. 132, and Tatham ». Le Roy, 2 Blatchf. 474.