Research is commonly divided into "applied" and "pure". This classification is arbitrary and loose, but what is usually meant is that applied research is a deliberate investigation of a problem of practical importance, in contradistinction to pure research done to gain knowledge for its own sake. The pure scientist may be said to accept as an act of faith that any scientific knowledge is worth pursuing for its own sake, and, if pressed, he usually claims that in most instances it is ually found to be useful. Most of the greatest discoveries, such as the discovery of electricity, X-rays, radium and atomic energy, originated from pure research, which allows the worker to follow unexpected, interesting clues without the intention of achieving results of practical value. In applied research it is the project which is given support, whereas in pure research it is the man. However, often the distinction between pure and applied research is a superficial one as it may merely depend on whether or not the subject investigated is one of practical importance, For example, the investigation of the life cycle of a protozoon in a pond is pure research, but if the protozoon studied is a parasite of man or domestic animal the research would be termed applied. A more fundamental differentiation, which corresponds only very roughly with the applied and pure classification is (a) that in which the objective is given and the means of obtaining it are sought, and (b) that in which the discovery is first made and then a use for it is sought.
There exists in some circles a certain amount of intellectual snobbery and tendency to look contemptuously, on applied investigation. This attitude is based on the following two false ideas: that new knowledge is only discovered by pure research while applied research merely seeks to apply knowledge already available, and that pure research is a higher intellectual activity because it requires greater scientific ability and is more difficult. Both these ideas are quite wrong. Important new knowledge has frequently arisen from applied investigation; for instance, the science of bacteriology originated largely from Pasteur’s investigations of practical problem in the beer, wine and silkworm industries. Usually it is more difficult to get results in applied research than in pure research, because the worker has to stick to and solve a given problem instead of following any promising clue that may turn up. Also in applied research most fields have already been well worked over and many of the easy and obvious things have been done. Applied research should not be confused with the routine practice of some branch of science where only the application of existing knowledge is attempted. There is need for both pure and applied research for they tend to be complementary.
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