Philosophy of Being and Knowledge

Philosophy of Science

The Evolutionary Theory of Science by Stephen Toulmin

The British philosopher Stephen Edelston Toulmin (1922-2009) proposed his own conception of the nature of science, applying Darwinian evolutionary principles. He critiqued two extreme positions—absolutism and relativism. Adherents of the former claim that truth is immutable and absolute across all times and contexts. Relativists, on the other hand, argue that truth is relative: each time and context has its own truth, making the defense of absolute propositions irrelevant. Toulmin, however, believed that truth unfolds across different fields of argumentation. Each field is a distinct sphere with its own standards. What was considered beautiful by people thousands of years ago is not necessarily deemed beautiful today. Yet, the very concept of beauty remains unchanged. Thus, there exist truths that are eternal and unchanging, as well as those that evolve with time and context. Not all truths are absolute, as absolutists claim, and not all are relative, as relativists assert. Toulmin referred to truths dependent on their fields as "field-dependent" and those that remain constant and absolute as "field-invariant."

While field-invariant truths are constant and unchanging, there is no point in seeking patterns in their emergence. The situation is different for field-dependent truths. Since they change according to their fields, some underlying pattern must govern these changes. In search of an answer, Toulmin turned to Darwin's theory of evolution, which posits that organisms well-adapted to their environment survive, while those that do not adapt perish. Toulmin applied this explanation to science, viewing the history of science as a continuous emergence of diverse theories. Theories that effectively explain reality and are practically useful—those well-adapted to their conditions—survive, while those that do not adapt perish. However, the rule of evolution applies exclusively to field-dependent truths. Field-invariant truths remain true at all times and provide meaning to field-dependent truths.