The Gordian Knot is a legend of Phrygian Gordium associated with Alexander the Great. It is often used as a metaphor for an intractable problem solved easily by cheating or ‘thinking outside the box.’
In Objective Knowledge: An Evolutionary Approach, Karl Popper wrote, ‘I may be mistaken; but I think that I have solved a major philosophical problem: the problem of induction.’ Popper’s solution was quite novel; he proposed that induction is superfluous to the scientific method and the growth of knowledge.
In Popper’s view, scientific hypotheses are unjustifiable conjectures discovered through bold and creative speculation. While the discovery of a hypothesis might be inspired by empirical observation, it might also be inspired by analogy, confusion, cranial trauma, or whatever else. In any case, no satisfactory logic of induction can be formulated to derive scientific hypotheses from empirical observations.
What role, then, do empirical observations serve? Popper’s answer was that although empirical observations cannot, in principle, discover or verify scientific hypotheses, they might falsify them. Observations, particularly experiments, serve to challenge hypotheses by exposing them to potential refutation. These falsifying inferences are exemplified by the deductive rule of modus tollens.
Popper’s solution to the problem of induction delivers a double whammy: not only is an inductive logic impossible to formulate satisfactorily, but it would be redundant anyway. Induction is neither necessary for the discovery of new hypotheses nor useful in their critical evaluation. Popper proposed we replace the so-called inductive methods of science with an evolutionary method of conjecture and refutation.
If a solution to the problem of induction is expected to explain how induction is both possible and justified, Popper was wrong: he did not solve the problem of induction. Indeed, he the denied induction root and branch. Popper’s problem, then, was to explain the growth of knowledge, especially scientific knowledge, in a way that did not depend on induction at all.
If Popper succeeded, then he left us with a competing vision of the growth of knowledge in which the problem of induction never arises.
Popper cut the Gordian knot. Implicit assumptions and expectations that defined the game of philosophy were violated–his solution to the problem of induction was, in short, a cheat. Initial excitement and bewilderment later turned to scorn and ostracism as philosophers realised they had been duped. Popper was not playing by the rules!
Critics began retying the knot in haste. The implicit assumptions and expectations that Popper had sought to overthrow–psychologism, inductivism, and justificationism–were reaffirmed.
Popper’s evolutionary method was shoehorned into the existing paradigm and, unsurprisingly, found wanting. Superficial resemblance between corroboration and induction was exaggerated; accusations of implicit inductive inferences came think and fast; Popper’s own fallibilism was held against him to “demonstrate” the impossibility of falsification. No misrepresentation nor strawman was too flagrant to be accepted and echoed at even the highest levels of academia.
Popper seemingly misunderstood his role as philosopher. After all, the implicit assumptions that he fought against were also the fertile soil from which the perennial problems of philosophy grow–problems that are to be cherished and protected. They are the source of much employment and scholarly publication; and perhaps too many egos are now at stake to let anyone find a solution. Popper broke the rules of his community and paid the price.
Popper is often given lip-service as one of the great philosophers of the twentieth century, but he is now only a myth relegated a pedagogic convenience–a cautionary tale that adult philosophers tell children philosophers to scare them into good thinking.