The Scientific Method

It is a widely held view that science is basically an inductive-empirical method for obtaining knowledge. There is some justification for this popular assessment, because scientists do put great store in specific facts, observations, and sense data. However, a careful analysis of the scientific method reveals that what the scientist does in the search for knowledge is more accurately described in terms of a particular combination of empirical and rational procedures.

Scientific epistemology is both complex and controversial, but an effort will be made to present a concise philosophical analysis of the scientific method as a distinctive theory of knowledge.

Simply stated, the scientific method is one way of going about the business of acquiring knowledge. A definite sequence of procedures is followed in order to find specific kinds of answers to specific kinds of questions. Perhaps the epistemology of the scientific method can be discussed most profitably by directing our attention to a typical formula in which the sequential steps in the thought process are arranged. While there are many different versions of the "scientific method," the bare outlines of the procedure can be described in the following six steps:
a. Awareness and definition of a problem.
b. Observation and collection of relevant data.
c. Organization or classification of data.
d. Formulation of hypothesis.
e. Deductions from the hypotheses.
f. Testing and verification of the hypotheses.

Let us consider each of the six steps separately so that our analysis can be incisive and especially so that we can point more directly to the empirical and the rational elements of the scientific way of knowing.

a. Awareness of a problem. The world that the scientist looks on is made up of an almost infinite numbers of separate facts and events that in and of themselves exhibit no meaningful order. It is only when people encounter obstacles as they seek to deal intelligently with that world that thought takes shape. In other words, people somehow create problems and propose what they think are answerable questions. Without a clearly defined problem, there is no way of knowing what particular facts to collect. The scientific method stresses at the outset the clear and precise statement of a problem.

The initial phase of the scientific method assumes a world of empirically observable objects and events, but people impose on that world an order or context by which a limited range of perceived facts can be given meaning. The rationalist's claim is supported at this stage by the argument that it is reason that structures and guides investigation. Reason provides a "sense of the problem" without which it would be impossible to order or arrange facts in any intelligible way. If there is no question, how can there be an answer?

b. Observations and collection of data. Observation and the collection of data is the most familiar step in the scientific method. It is because so much of the specific activity of scientists is directed toward the gathering of data that many have come to equate science with fact collecting. The meticulous observations made possible by ingenious instruments give dramatic support to the conception of science as a basically empirical and inductive procedure. The reliance on direct or indirect sense perceptions and the demand for precise observation conspire to keep our attention on the empirical aspect of scientific investigation.

c. Organization, or classification, of data. The organization, or classification of data, phase of the scientific method stresses the arrangement of facts into groups, kinds, and classes. In all the particular sciences, the attempt to enumerate, analyze, compare, and contrast the relevant data depends on the establishment of systems of classification. The special study that develops and elaborates adequate systems of classification is called taxonomy, and modern scientists work continually to perfect their specialized taxonomies. But it is important to remember that categories or classes are not facts. Rather, they are the conceptual boxes into which the facts are inserted so that those facts can be organized according to their relevance and thus be given general names and meanings. Both empirical and rational elements are evident at this stage in the procedure.

d. Formulation of hypotheses. Facts do not speak for themselves. In the world confronted by science, a group of molecules or cells does not jump up and down, wave, whistle, and declare, "Look at me! Here! I am a rock, or a tree, or a horse." What a thing is depends on the labels assigned to that thing. How a thing comes to be explained depends on the conceptual relationships with which it is viewed. This fact brings us to one of the most difficult aspects of scientific methodology: the role of the hypothesis.

Hypotheses are tentative statements about relationships between things. These hypothetical relationships are proposed in the form of working guesses, or theories, according to which it is hoped that explanations will become possible. Hypotheses are typically suggested on a trial-and-error basis. They may be merely reasonable hunches, or they may be extensions of previously verified hypotheses to new data. In either case, hypotheses serve to frame the data in such a way that a presumed relationship is set up and a possible explanation suggested. A hypothesis is usually stated in the form of an "if X, then Y proposition. If human skin lacks pigmentation, then it will burn quickly when exposed to the direct rays of the sun. This hypothesis offers a tentative explanation of at least some of the relationships between skin pigmentation and sunlight. The hypothesis also tells us what conditions must prevail and what observations are needed if we wish to verify our original working guess.

In the concept of the hypothesis, so crucial to the scientific method, we can find both empirical and rational elements. There must be empirical data in the form of observable and measurable facts, and there must also be conceptual categories by which the kinds of data are logically separated and arranged so that probable interconnections can be suggested.

e. Deductions from hypotheses. Those who think of science as a method of strictly inductive reasoning that proceeds directly from facts to explanations should pay special attention to the function of hypotheses. Hypotheses establish logical propositions from which it is possible to infer, or deduce, relationships between the particular things being investigated. Furthermore, hypotheses can assist us in predicting and discovering new facts. The deductive reasoning points out that much of what we call scientific knowledge is theoretical rather than empirical in nature and that prediction is dependent on a form of syllogistic logic.

f. Testing and verification of hypotheses. Verification in science means testing alternative hypotheses by actual observation or experimentation. Final reference is made to the facts. If the facts do not bear out one hypothesis, another hypothesis is selected, and the process is repeated. The last course of appeal is, however, the empirical data; scientific generalizations, or laws, must meet the test of experience. At this point, one might not be surprised to find the pragmatist applying the test of consequences as the ultimate criterion in evaluating the scientific method: Does it work? Neither do the rationalists surrender the field during the verification phase. They point out that a hypothesis is scientifically acceptably only if it is found to be consistent with previously established verified hypotheses (a reference to the coherence theory of truth).

To summarize: the scientific method is a theory of knowledge by which people seek particular kinds of answers to particular kinds of questions. The method emphasizes a rigorous sequence of procedures by which a continuously expanding and self-correcting body of knowledge is achieved. The scientific method rests on the assumption that there are discoverable regularities in the relationships among phenomena and that the human sense organs (or the instruments by which they are refined) are basically adequate. Through the systematic organization and verification of observations, people are able to accumulate a growing body of knowledge that has a very high probability of being true. The scientific method does not claim to be a method by which one can arrive at any changeless or ultimate knowledge.