Geomorphology as science: the role of theory

Because geomorphology is a science, it is permeated by theory. Overt recognition of this actuality is frequently resisted by geomorphologists. Earth history does not represent an alternative to earth science, it is an essential component of earth science. In its broadest sense science seeks to discover new knowledge through a two-stage activity involving the creation and justification of ideas (theory). Deduction is generally regarded as the only logically-consistent method of justifying ideas. The creation of ideas is a much more controversial topic. Some methodologists deem it beyond logic; certainly deductive arguments, which are nothing more than formal, logical expressions of theory, play no role in the conception of new ideas. Many earth scientists generate possible explanations of observed phenomena based on abductive reasoning. Others advocate reliance on purported forms of "pure" induction, such as serendipity and intuition, in which observations assume primacy over theory. Besides lacking consistency and educability, the latter posture is flawed because it mistakenly implies that becoming well-versed in theory is irrelevant to or impedes scientific discovery. Irrational or subjective factors play a role in the creation of ideas, but it is erroneous to claim that these factors are divorced from theory. Science is first and foremost a cognitive activity; thus, the primacy of observations in science is a myth. All observations are theory-laden in the sense that the act of observation inherently involves interpretation and classification, both of which can only occur within the context of theoretical preconceptions. Even discoveries based on unexpected observations require the fortunate investigator to recognize the theoretical importance of what is seen or measured. The most useful view of geomorphology as a science is one in which theory is seen as central, but fragile, and in which theory and observation are viewed symbiotically with theory providing the generative force and observation providing a vital policing role. Much of the current debate in geomorphology centers around differences in characteristics of theory, type of scientific arguments, and metaphysical perspectives among investigators working at different temporal scales. Full recognition and understanding of these differences are essential for developing a unified approach to the science of geomorphology.