JANUAKT 17, 1913] 



SCIENCE 



105 



place to a universe of law. Order replaces 

 disorder, necessity supplants chance in the 

 thoughts of men, until the realm of experience 

 is finally viewed as a consistent and rational 

 whole, wherein every change is conditioned by 

 uniform antecedents and expressible in terms 

 of natural law. 



The application of this point of view, it 

 may logically be said, implies a preliminary 

 treatment in which phenomena are organized 

 in a unitary system of classifications on the 

 basis of specific resemblances and differences. 

 But the process of defining and naming, of 

 conceiving individuals in terms of fixed char- 

 acteristics and referring each to its place in a 

 logical scheme may be said merely to provide 

 the data for the mind's final operation whose 

 field is the interaction of things^ The world 

 is treated dynamically as well as statically. 

 The subject of specific characteristics is also 

 the origin of certain effects. It has its place 

 in a causal series as well as in a classificatory 

 system. The logical relations of likeness and 

 difference must be supplemented by the em- 

 pirical relations of genesis and historical 

 origin. To connect events in this way is to 

 explain them. The world as a system of ob- 

 jects can only be described; to be explained 

 it must be conceived as a system of orderly 

 successions in time. The universal principle 

 of explanatory science is thus to be found in 

 what is termed the conception of causal rela- 

 tion, since it is simply the generalization of 

 this idea of uniformity in historical succes- 

 sion. Natural science therefore rests finally 

 upon the assumption of mechanism and ex- 

 cludes all other conceptions. 



Historically the explanations of science 

 have been supplemented at every stage by 

 principles dependent upon the assumption of 

 purpose or function, but every such recourse 

 represents a failure in the scientific under- 

 taking or a loss of the scientist's vision. Its 

 interpolation indicates either the presence of 

 an unresolved problem or a confusion as to 

 the nature of scientific explanation. The 

 ideal of science is, from the methodological 

 point of view, perfectly clear; it is to deter- 

 mine the atomic constitution of the world and 



to formulate the mechanics of its changes. 

 The particular constitution of the units and 

 formulas with which the scientist works may 

 vary from age to age, since these are neces- 

 sarily provisional and relative to the level of 

 analysis attained at any given time; but the 

 formal ideal of all analysis is unaffected by 

 such changes and remains theoretically con- 

 stant. The unit must be simple, the formula 

 universal. No ultimate difference among the 

 constitutive units, and no partition of the 

 world between irreducible forms of change can 

 be admitted. This is the fundamental as- 

 sumption from which the scientist can not 

 allow himself to be swerved by any complica- 

 tion of the phenomena to be treated or any 

 difficulty in their resolution. 



Such a postulate can be maintained only in 

 view of the fact that science is not an at- 

 tempt to exhaust the account of reality, and 

 that its presuppositions constitute but a neces- 

 sary methodological delimitation. Reality is 

 viewed by man in a series of differing rela- 

 tions, each of which involves a specific set of 

 such presuppositions. With none of these 

 other points of view, however, can science have 

 even contact; and the penetration of his own 

 field by the conceptions to which they give 

 rise can mean only the disorganization of his 

 results. 



The traditional form in which this adultera- 

 tion of scientific method has been manifested 

 is an employment of the conception of creative 

 spirits, essences and powers as explanatory 

 formulae. Angels and demons, entelechies 

 and souls, function and purpose, force and 

 will; vitalistic, morbific and soporific agencies 

 have been invoked in turn as explanatory 

 hypotheses. It may be that human reflection 

 has need of this whole class of conceptions in 

 its complete review of reality; but in the spe- 

 cial work which science in general undertakes 

 they can afford no help whatever. Each re- 

 lapse into such modes of thought marks the 

 point at which scientific analysis has stopped 

 and amounts to nothing more than the con- 

 fused recognition of an irreducible element in 

 experience. This the scientist must recognize 

 as well as any other, but it is absurd to make 



