It is not a criticism of reason to acknowledge that no reasoning person or group can have a synoptic view of the world or of society that would enable him or it to rationally plan everything. The faculty of reason is packaged within individual human beings, and no mountaintop exists from which one could see and know all that it would take to plan a society or an economy in the interest of all its participants. The result of attempting to do so would inevitably be what Ludwig von Mises called “planned chaos.” This is what F. A. Hayek, Mises’s student, also worked so hard to explain.
But when individuals operate and cooperate in a free society and marketplace, their small portion of knowledge, articulated and tacit, becomes accessible to all, mostly through the price system. Mises and Hayek showed this in the great socialist-calculation debate of the ’20s and ’30s.
Reason is powerfully efficacious in that it enables us to perceive and understand the world that exists independently of us. It’s a time-consuming, effortful, and piecemeal pursuit that is subject to never-ending rebuttal, refutation, and revision. Does reason have limits? Of course. Everything has limits. A is A means that A is not non-A. But that is hardly a criticism of reason. It’s an invitation to understanding and a notice to avoid what Hayek called the “abuse of reason.” (See his The Counter-Revolution of Science: Studies on the Abuse of Reason.)