THEORY AND PRACTICE.

Progress, Volume II, Issue 2, 1 December 1906, Page 60

THEORY AND PRACTICE.

By Peter Ellis \\ Ellington

How often the remark is heard " Yes, it sounds all right m theory, but it does not work out in practice" , in such cases which is at fa"ult ? Certainly not practice, for as Sir Humphry Davy declared "one fact is worth a thousand theories" Now, there are " theories and — theories," as the French say, and if theory and practice fail to agree it is mainly because the theory is incorrect, and not that theory and practice are incompatible Theory and practice always agree when theory is sound ; therefore, " practical " engineers should not despise theory because it sometimes fails to " show the reason why." It may seem peculiar, but sound theory is founded on fact, and it is a happy combination when practice and theory go hand-in-hand, and an engineer with a wellbalanced mind commanding this combination is likely to be more successful than either the theorist or the practical engineer. Depend upon it, that when theory does not fit m with practice, it is not that theory, as theory, is of less value than practice, but because it has fallen short of its true value in that particular instance, or has been propounded on a false basis, since every fact must have its true theory somewhere, whether discovered and elaborated, or not. Probably the reasons why so few successful inventors spring from our colleges and so many come from practical men is that the practical man is in possession of ascertained facts based on his experience, which cannot be gainsaid ; and whether these facts can be successfully theorised on or not, they are facts ; and the practical man knows that if he bases his ideas on these solid facts he is on safe ground — hence the great value of actual experiment. Actual experiment may introduce important elements which theory may have overlooked or wrongly calculated ; on the other hand, the inventor without theory, especially if his experience of facts is limited — and no man can experience all the facts in the engineering world — will have a hard row to hoe to bring his ideas to fruition. There is not the slightest doubt but that some theories are absolutely sound and consistent with solid facts, but since all progress is the result of evolution, theories must evolve, and some of the theories to-day must disappear and give place to others, as surely as the sun shines and that day follows night. Why are scientists so anxious to get to the North Pole ? Why not be satisfied with their theory ? Simply because they are in the habit, and properly so, of proving their theories by absolute fact, based on experiment or actual experience. Who -would have divined the existence of electrical energy — now such a handmaid of our civilisation — apart from the experience, accidental or otherwise, of the effect of electricity on our senses ? This is a self-evident fact, without a suspicion of theory. Theory has its place, but if we pin our faith wholly to it our progress will be slow and the practical experimentalist will distance us in the race of improvements, although he may wade through a maze of intricacies.