It’s not exactly predestination, man. Predestination is usually regarded as a religious concept associated with John Calvin. Although both Calvin and Hayek dismissed the idea of free will, Calvin’s predestination held that our ultimate course in life and in salvation is laid out before us with unwavering certainty by God:

When men do come into the way of righteousness, or return into it, by means of holy correction or rebuke, who is it that works salvation in their hearts but He who ‘giveth the increase,’ whoever soweth, or whoever watereth? No free will of man can resist Him that willeth to save. Wherefore, we are to rest assured that no human wills can resist the will of God, who doeth according to His will all things in heaven and in earth, and who has already done by His will the things that shall be done. No will of men, we repeat, can resist the will of God, so as to prevent Him from doing what He willeth, seeing that He doeth what He will with the wills themselves of all mankind. And when it is His will to bring men by any certain way that He may please, does He bind their bodies, I pray you, with chains? O, no! He works within; He takes hold of their hearts within; He moves their hearts within; and draws them by those, now, new wills of their own which He has Himself wrought in them [John Calvin, “A Treatise of the Eternal Predestination of God Etc., Etc.“].

Hayek, on the other hand, had a much more complex and anarchic type of determinism in mind:

[I]t should not be difficult now to recognize that although Hayek rejects the idea of free will, he accepts the idea of a subjective will; that is, a willfulness unique to each individual. It should also not be difficult to recognize the predictive limitations applying to explanations of such a will. In fact, Hayek rejects the possibility of “specific prediction” in the case of the individual will and finds that such a goal is “completely unjustified” [. . .] In other words, even though we may know the general principle by which the complex adaptive system we call the mind is causally determined by evolutionary processes, this does not mean that a particular human action can ever be introspectively recognized as the necessary result of a particular set of facts. Indeed, Hayek maintains that we are in no better position to predict the specific future motions of our mind than we are “able to predict the shape and movement of [a] wave that will form on the [surface of the] ocean at a particular place and moment in time” [Gary T. Dempsey, “Hayek’s Evolutionary Epistemology, Artificial Intelligence, and the Question of Free Will“].

In order to make any kind of certain prediction about individual action, if Hayek’s theories were true, you’d have to understand not only how the brain chemistry of the individual in question operates, but you’d have to know how the brain chemistry of every other living creature in the world works, and how every natural phenomenon in the universe will play out, with absolute detailed certainty. That’s the only way you could know both how an individual would respond to a given set of circumstances — and to know exactly the sets of circumstances that the given individual would encounter.

So, according to Hayek’s theories of evolutionary epistemology, in order to predict a single person’s actions with certainty, you’d have to know everything about everything. In other words, you’d have to be God. Maybe it’s not so different from Calvin’s predestination after all . . .