Now in loosening a physical knot it is evident that one who is unacquainted with this knot cannot loosen it. But a difficulty about some subject is related to the mind as a physical knot is to the body, and manifests the same effect. For insofar as the mind is puzzled about some subject, it experiences something similar to those who are tightly bound. For just as one whose feet are tied cannot move forward on an earthly road, in a similar way one who is puzzled, and whose mind is bound, as it were, cannot move forward on the road of speculative knowledge. Therefore, just as one who wishes to loosen a physical knot must first of all inspect the knot and the way in which it is tied, in a similar way one who wants to solve a problem must first survey all the difficulties and the reasons for them.
[Thomas Aquinas, Commentary on Aristotle's Metaphysics, Rowan, tr. Dumb Ox (Notre Dame, IN: 1995) p. 128.]
Recognizing this requires recognizing that the 'history' and 'problems' sides of philosophy, often treated as distinct approaches, need to be integrally related. I've previously called this the problem of the philosophical problem (and here); it's still one of the key issues in the study of the history of philosophy. Philosophical problems are knots, knots must be tied, and the tying of the knot is the history of it; without seeing how the knot was tied one simply does not know what kind of knot it really is.
