[Footnote 1: Quoted by Thomson from an address on "Technical Chemistry" by C. E. Munroe.]
Practical life has been continually enriched by theoretical inquiry. Scientific descriptions increase in value as they become absolutely impersonal, absolutely precise, and especially as they become condensed general formulas, which will be applicable to an infinite variety of particular situations. And such descriptions are necessarily abstract and theoretical.
Analysis of scientific procedure. Scientific method is merely common sense made more thoroughgoing and systematic. Reflection of a more or less effective kind takes place in ordinary experience wherever instinctive or habitual action is not adequate to meet a situation, whenever the individual has a problem to solve, an adjustment to make. Thinking, of some kind, goes on continually. Scientific thinking merely means careful, safeguarded, systematic thinking. It is thinking alert and critical of its own methods. As contrasted with ordinary common-sense thinking, it is distinguished by "caution, carefulness, thoroughness, definiteness, exactness, orderliness, and methodic arrangement." We think, in any case, because we have to, being creatures born with a set of instincts not adequate to meet the conditions of our environment. We can think carelessly and ineffectively, or carefully and successfully.
Scientific method, or orderly, critical, and systematic thinking, is not applicable to one subject-matter exclusively. Examples are commonly drawn from the physical or chemical or biological laboratory, but the elements of scientific method may be illustrated in the procedure of a business man meeting a practical problem, a lawyer sifting evidence, a statesman framing a new piece of legislation. In all these cases the difference between a genuinely scientific procedure and mere casual and random common sense is the same.
Science is nothing but trained and organized common sense, differing from the latter only as a veteran may differ from a raw recruit: and its methods differ from those of common sense only so far as the guardsman's cut and thrust differ from the manner in which a savage wields his club. The primary power is the same in each case, and perhaps the untutored savage has the more brawny arm of the two. The real advantage lies in the point and polish of the swordsman's weapon; in the trained eye quick to spy out the weakness of the adversary; in the ready hand prompt to follow it on the instant. But, after all, the sword exercise is only the hewing and poking of the clubman refined and developed.
So, the vast results obtained by science are won by ... no mental processes, other than those which are practiced by everyone of us, in the humblest and meanest affairs of life. A detective policeman discovers a burglar from the marks made by his shoe, by a mental process identical with that by which Cuvier restored the extinct animals of Montmartre from fragments of their bones.... Nor does that process of induction and deduction by which a lady finding a stain of a peculiar kind upon her dress, concludes that somebody has upset the inkstand thereon, differ, in any way, in kind, from that by which Adams and Leverrier discovered a new planet.
The man of science, in fact, simply uses with scrupulous exactness the methods which we all, habitually and at every moment, use carelessly; and the man of business must as much avail himself of the scientific method—must as truly be a man of science—as the veriest bookworm of us all.[1]
[Footnote 1: Huxley: Lay Sermons, Addresses, and Reviews, pp. 77, 78 (in "The Educational Value of the Natural History Sciences").]
The scientific procedure becomes, as we shall see, highly complicated, involving elaborate processes of observation, classification, generalization, deduction or development of ideas, and testing. But it remains thinking just the same, and originates in some problem or perplexity, just as thinking does in ordinary life.
Science and common sense. It is profitable to note in some detail the ways in which scientific method, in spirit and technique, differs from common-sense thinking. It is more insistent in the first place on including the whole range of relevant data, of bringing to light all the facts that bear on a given problem. In common-sense thinking we make, as we say, snap judgments; we jump at conclusions. Anything plausible is accepted as evidence; anything heard or seen is accepted as a fact. The scientific examiner insists on examining and subjecting to scrutiny the facts at hand, on searching for further facts, and on distinguishing the facts genuinely significant in a given situation from these that happen to be glaring or conspicuous. This is merely another way of saying that both accuracy and completeness of observation are demanded, accuracy in the examination of the facts present, and completeness in the array of facts bearing on the question at hand.