AmosWEB.com has an explanation of Game Theory here.
I begin rambling here. When I interact with other people, do I always take into consideration their actions? When I go to the store, do I plan my visit so that I avoid some people and not others? How do I know where to park at the store? If I anticipate rival responses, then I'm acting strategically? Some people believe that all human interaction is strategic.
Now, Hayek concludes that equilibrium occurs naturally like geese flying in formation or other self-ordering lists. But if I anticipate rival responses I might not act naturally so that I can influence the outcome more favorably. This is especially true with committee voting where I might vote strategically one time then vote by my preferences another. A brilliant discussion of this tactic is found at Electowiki.
As long as there are few rational actors in the interaction, I can influence the outcome and defeat the natural equilibrium that Hayek suggests and the wrong equilibrium will emerge or there will be two equilibriums.
When the government creates a new tax law, people change their behavior to avoid paying the new taxes. If people change their behavior in response to government regulations, I'm voting for limited government intervention in markets.