found an explanation for every new puzzle which presented itself. This dis- position has propagated itself, and has come down to our time as an intellec- tual predilection, though the compass- The Method of Multiple ing of the entire horizon of knowledge has long since been an abandoned af- Working Hypotheses fectation. As in the earlier days, so still, it is the habit of some to hastily conjure up an expIanation for every With this method the dangers of parental new phenomenon that presents itself. Interpretation rushes to the forefront affection for a favorite theory can be circumvented. as the chief obligation pressing upon the putative wise man. Laudable as the T. C. Chamberlin effort at explanation is in itself, it is to be condemned when it runs before a serious inquiry into the phenomenon itself. A dominant disposition to find out what is, should precede and crowd As methods of study constitute the in Euclid precisely as laid down is an aside the question, commendable at a leading theme of our session, I have illustration of the former; the demon- later stage, “How came this so?” First chosen as a subject in measurable con- stration of the same proposition by a full facts, then interpretations. sonance the method of multiple work- merhod of one’s own or in a manner ing hypotheses in its application to distinctively individual is an illustration investigation, instruction, and citizen- of the latter; both lying entirely within Premature Theories ship. the realm of the known and the old. There are two fundamental classes Creative study, however, finds its The habit of precipitate explanation of study. The one consists in attempt- largest application in those subjects in leads rapidly on to the development of ing to follow by close imitation the which, while much is known, more re- tentative theories. The explanation of- processes of previous thinkers, or to mains to be known. Such are the fields fered for a given phenomenon is nat- acquire by memorizing the results of which we, as naturalists, cultivate: and urally, under the impulse of self-con- their investigations. It is merely sec- we are gathered for the purpose of sistency, offered for like phenomena as ondary, imitative, or acquisitive study. developing improved methods lying they present themselves, and there is The other class is primary or creative largely in the creative phase of study, soon developed a general theory ex- study. In it the effort is to think in- though not wholly so. planatory of a large class of phenom- dependently, or at least individually, in Intellectual methods have taken three ena similar to the original one. This the endeavor to discover new truth, phases in the history of progress thus general theory may not be supported or to make new combinations of truth, far. What may be the evolutions of by any further considerations than or at least to develop an individualized the future it may not be prudent to those which were involved in the first aggregation of truth. The endeavor is forecast. Naturally the methods we now hasty inspection. For a time it is likely to think for one’s self, whether the urge seem the highest attainable. These to be held in a tentative way with a thinking lies wholly in the fields of three methods may be designated, first, measure of candor. With this tentative previous thought or not. It is not neces- the method of the ruling theory; sec- spirit and measurable candor, the mind sary to this habit of study that the sub- ond, the method of the working hypoth- satisfies its moral sense, and deceives ject-material should be new; but the esis; and, third, the method of mul- itself with the thought that it is pro- process of thought and its results must tiple working hypotheses. ceeding cautiously and impartially to- be individual and independent, not the In the earlier days of intellectual de- ward the goal of ultimate truth. It mere following of previous lines of velopment the sphere of knowledge fails to recognize that no amount of thought ending in predetermined re- was limited, and was more nearly with- provisional holding of a theory, so long s&s. The demonstration of a nroblem in the compass of a single individual; as the view is limited and the investi- Thomas C. Chamberlin (1843-1928). a geologist, and those who assumed to be wise gation partial, justifies an ultimate con- was president of the University of Wisconsin at men, or aspired to be thought so, felt viction. It is not the slowness with the time this lecture was written. Later he was professor and director of the Walker Museum of the need of knowing, or at least seem- which conclusions are arrived at that the University of Chicago. In 1893 he founded the Journal of Geology, which he edited until ing to know, all that was known as a should give satisfaction to the moral his death. In 1908 he was president of the AAAS. justification of their claims. So, also, sense, but the thoroughness, the com- The article is reprinted from Science (old series), 15, 92 (1890). there grew up an expectancy on the pleteness, the all-sidedness, the impar- Reprints of this article are available. part of the multitude that the wise and tiality, of the investigation. Prices (cash with order): the learned would explain whatever It is in this tentative stage that the 1 50 cents (or 25 cents and stamped, self-addressed envelope) new thing presented itself. Thus pride affections enter with their blinding in- 2 to 9 45 cents each IO to 24 30 cents each and ambition on the one hand, and fluence. Love was long since represent- 25 or more 20 cents each expectancy on the other, developed the ed as blind, and what is true in the Address orders to AAAS, Chamberlin Reprints, 1515 Massachusetts Ave., NW, Washington, D.C. putative wise man whose knowledge personal realm is measurably true in 20005. boxed the compass, and whose acumen the intellectual realm. Important s,;., 154 SCIENCE: VOL. 148.j : +he intellectual affections are as stimuli to survive, and to maintain its domi- I -- and as rewards, they are nevertheless nance, because the phenomena them- dangerous factors, which menace the selves, being largely subjective, were integrity of the intellectual processes. plastic in the hands of the ruling idea; The moment one has offered an origi- but so soon as investigation turned it- nal explanation for a phenomenon self earnestly to an inquiry into nat- which seems satisfactory, that moment ural phenomena, whose manifestations affection for his intellectual child are tangible, whose properties are springs into existence; and as the ex- rigid, whose laws are rigorous, the de- planation grows into a definite theory, fects of the method became manifest, hi‘; parental affections cluster about his and an effort at reformation ensued. int~l[ectLlZll offspring, and it grows more The first great endeavor was repres- and more dear to him, so that, while sive. The advocates of reform insisted he holds it seemingly tentative, it is that theorizing should be restrained, still lovingly tentative, and not im- and efforts directed to the simple de- partially tentative. So soon as this pa- termination of facts. The effort was to rcnt;ll affection takes possession of the make scientific study factitious instead mincl. there is a rapid passage to the of causal. Because theorizing .in narrow adoption of the theory. There is an lines had led to manifest evils, theorizing unconscious selection and magnifying was to be condemned. The reformation of the phenomena that fall into har- urged was not the proper control and mony with the theory and support it. Thomas Chrowder Chamberlin was noted utilization of theoretical effort, but its and an unconscious neglect of those for his contributions to glaciology and for suppression. We do not need to go his part in formulating the Chamberlin- that fail of coincidence. The mind Moulton (planetesimal) hypothesis of the backward more than twenty years to lingers with pleasure upon the facts origin of the earth. find ourselves in the midst of this at- that fall happily into the embrace of tempted reformation. Its weakness lay the theory, and feels a natural cold- in its narrowness and its restrictive- nc,s toward those that seem refractory. vestigator dominated by a false ruling ness. There is no nobler aspiration Instinctively there is a special se:lrch- idea. His very errors may indeed stimu- of the human intellect than desire to ing-out of phenomena that support it. late investigation on the part of oth- compass the cause of things. The dis- for the mind is led by its desires. ers. But the condition is an unfortu- position to find explanations and to There springs up, also, an unconscious nate one. Dust and chaff are mingled develop theories is laudable in itself. pressing of the theory to make it fit with the grain in what should be a It is only its ill use that is reprehensi- the facts, and a pressing of the facts winnowing process. ble. The vitality of study quickly dis- to make them fit the theory. When appears when the object sought is a these biasing tendencies set in, the mind mere collocation of dead unmeaning rapidly degenerates into the partiality Ruling Theories Linger facts. of paternalism. The search for facts, The inefficiency of this simply re- the observation of phenomena and As previously implied, the method of pressive reformation becoming appar- their interpretation, are all dominated the ruling theory occupied a chief ent, improvement was sought in the hy affection for the favored theory un- place during the infancy of investiga- method of the working hypothesis.