Arsene Wenger and George Osborne don't seem to have much in common - only one of them has a qualification in economics - but they do. Both this week expressed a will to stay the course despite criticism. Osborne says that Moody's downgrade merely "redoubles" his determination to stay with his plan, and Wenger says he has never for "one second" considered resigning.

Such stubbornness is, of course, common in many walks of life. It is often the product of many cognitive biases, such as:

1. Bayesian conservatism. Both Wenger and Osborne have strong priors that they are right, and they regard evidence to the contrary as sufficiently noisy that it can be disregarded.

2.Ego involvement.For either man to step down would be a recognition not merely that a set of intellectual propositions is wrong, but that they themselves are not the men they thought they were - not the great Chancellor or great coach.

3. Gratification of enemies. An acknowledgement of error would be a victory for things they hate - Ed Balls in Osborne's case and financial doping in Wenger's. It's one thing to admit error in oneself; it's another to surrender to a loathsome foe.

4. Wishful thinking and overconfidence. It's surprisingly easy to believe things will turn out to one's advantage, especially if you think you're right anyway. So Osbone thinks business confidence will pick up because of low interest rates, and Wenger thinks his players will improve and that he can find new players to strengthen the squad.

It seems, then, as if Wenger and Osborne have much in common. Except for one thing - Wenger is a genius and Osborne, well, might not be. The difference, I suspect, lies in point 1. Wenger's prior that he knows best is founded upon things like: the fact that he's the only coach in 130 years to have taken a team through a whole top-division season unbeaten; the fact that no team that cost less to assemble has finished above Arsenal; and that he has turned countless players from unknowns to world stars. Osborne's prior is somewhat less well-founded.

Yes, Wenger might be biased. But sometimes, cognitive biases are a good thing, as they give us the strength to stick with a correct course in the face of adversity. The author who gives up after a few publishers reject her work, the businessman who gives up after a bank turns him down or sale falls through, and the musician who gives up after a few bad gigs might be behaving rationally. But rationality is not necessarily the road to success. As Richard Nisbet and Lee Ross wrote in Human Inference: Strategies and Shortcomings of Social Judgement, one of the earliest books on cognitive biases:

We probably would have few novelists, actors or scientists if all potential aspirants to these careers took action based on a normatively justifiable probability of success. We might also have few new products, new medical procedures, new political movements or new scientific theories.

If it weren't for the benefits of the biases that generate stubbornness, then, we'd have little art, music, business or science - and we'd probably be living under a Nazi dictatorship.

We should not, then, criticize Osborne for being stubborn. Stubbornness can be a virtue. The problem instead is that he's simply wrong.