Résumé
In sequential decision making contexts, with increasing information, people may differ in their attitudes towards sequential resolution of uncertainty. The first part of the paper shows that two opposite behavioral hypotheses are usually put forward in order to define rational behavior in such contexts. The first is Strotz's idea of "precommitment," which is in accordance with the expected utility hypothesis, and the second one, the "flexibility preference" hypothesis, which is not. I show that precommitment is rational as long as people are neutral against temporal risk. If they are not neutral, they exhibit "flexibility preference" or, equivalently, "irreversibility aversion." The second part of the paper is a critical survey on alternative theories of preference for flexibility.