ABSTRACT
To Davis most landscapes were composite and needed more than observation to disentangle their complexities. He believed firmly at the same time in the use of deduction and in the complicated nature of denudational chronologies. It is readily apparent that, not only did he recognize the theoretical model (i.e. deductive) characteristics of the cycle (e.g. 1905J, p. 152), but also considered this attribute to be an advantage:
The opinion prevails in many places that geology is chiefly an observational science. This is not correct. It is chiefly a speculative science, in that the great body of its statements go far beyond the field of observable fact into the field that can be reached only by means of speculative mental processes. The recognition of this truth carries with it two important consequences: first, that more systematic and thorough instruction in the non-observational side of geology should be given in the educational preparation of young geologists for expert work; second, that the published work of trained experts should make more explicit distinction between the inferred conclusions that they reach and the observed facts on which the conclusions are based.
(Davis, 1913M, pp. 686–7)