Evolutionary Theory: A Metaphysical Philosophy, Not an Empirical Science

The classification of evolutionary theory within the scientific method is a fundamental issue in the philosophy of science. In the 1970s, one of the most renowned philosophers of science of the twentieth century, the agnostic philosopher Karl Popper, declared that evolutionary theory does not rely on any tangible scientific evidence, describing it as a metaphysical research programme rather than a testable scientific theory.

I have come to the conclusion that Darwinism is not a testable scientific theory, but a metaphysical research programme.

Popper maintained this stance until shortly before his death, stating to Scientific American his dissatisfaction with and lack of conviction in the theory. The magazine published the admissions of Popper and other researchers in an article titled: "Darwin's Doubt: Why a group of non-religious scientists doubt evolutionary theory?".

The Problem of Tautology

Popper detailed his critique of evolutionary theory in his final book, Evolutionary Epistemology, where he presented the admissions of leading evolutionary scientists throughout its history. Among the most prominent of these testimonies is that of C. H. Waddington, who stated that evolutionary theory is nothing more than a tautology.

By tautology, he refers to circular reasoning or a statement that explains a thing by itself; the theory assumes every organism was naturally selected simply because it survived, which offers no genuine scientific explanation for the mechanism of origin.

Popper emphasizes that this critique intersects with the views of Ronald Fisher, the founder of modern Darwinism, as well as the geneticist J.B.S. Haldane, who acknowledge in various contexts the theory's lack of empirical scientific evidence and its total reliance on hypotheses, conjectures, and the mapping of links between organisms based solely on external similarities.