Hayek: Use of Knowledge

What is the problem we wish to solve when we try to construct a rational economic order? — F.A. Hayek, AER,XXXV, No.4;September,1945,pp.519-30.

Does Hayek mean(as he says) that we construct economic order? Isn’t economics a given natural occurance? Isn’t that what we mean when we say “the law of supply and demand” and such. That this occurs without our ability to alter its course.