Friday 25 January 2013

Dostoevsky on deciding what to do

There is an intriguing view of human decision-making and freedom in Dostoevsky's Notes from Underground, part 1, chapters 7 and 8. Here, I shall analyse an argument from chapter 7.

Dostoevsky starts with a question. Why do we, again and again, knowingly and deliberately act in ways that are contrary to our own advantage? He promptly moves on to another question. What is a person's advantage? Then he claims that there is an advantage that cannot possibly be included in any catalogue of advantages.

The advantage that cannot be included in any catalogue is that of making an unfettered choice, in defiance of any careful computation of advantage. The argument may be reconstructed as follows. (This reconstruction goes beyond what Dostoevsky says, in order to secure the argument against some obvious logical objections.)

1. Suppose that a person, D, is aware of the contents of a supposedly complete set, S, of advantages to him or her, along with information about their relative importance, about how to obtain the advantages, and about the possibilities for obtaining various combinations of them. "Advantages to D" has a broad meaning. It may include advantages of benefiting others, at no obvious gain to D. There is no suggestion that D need be selfish in making the best possible selection of advantages from S.

2. D can now make a careful computation of what to do, in order to maximize the net advantage to D.

3. D can also exercise freedom, by going against the result of the computation.

4. The exercise of freedom is in itself an advantage to D, but it cannot be the result of the computation, otherwise it would not be an assertion of D's freedom. D could freely decide to act in accordance with the result of the computation, but that would not be the kind of unfettered freedom that is required here. It would not assert D's ability to live unconstrained by such computations.

This argument does leave space for action in defiance of the result of the computation to be included in S. But defiance could not coherently appear as all or part of the result of the computation. Its inclusion in S would therefore be idle.

Suppose, first, that the computation produces a single recommendation, to act in defiance of the result of the computation. Compliance with the recommendation would amount to defiance of it, and defiance of it would amount to compliance with it. (There would be the additional, substantial, difficulty that D would not know what to do. "Act in defiance of a recommendation to eat healthily", would give D an idea of some specific action. "Do not do what this sentence tells you to do", would give no idea of any specific action.)

Now suppose that the computation produces several recommendations, say "Eat healthily", "Move to another city", and "Act in defiance of the result of the computation". If we read this list as a conjunction, as I think should, we find that D cannot comply with all conjuncts. Suppose that D eats healthily and moves to another city. Then if D complies with the final conjunct, it can only be by defying that conjunct, since that is the only remaining way to break the terms of the conjunction. If, on the other hand, D defies the final conjunct, then D must comply with the whole conjunction, which must mean complying with the final conjunct, as well as with the other two.

The one apparently coherent option would be to defy either or both of the first two conjuncts, and thereby comply with the third. But on closer inspection, we can see that this would not work either. The reason is that it would be known in advance that "Act in defiance of the result of this computation" would amount to "Discard at least one of the specific prescriptions". Given that acting in defiance of the computation was considered to be an advantage, a member of S, this discard would be required in order to yield the optimal solution, if the prescription to act in defiance of the result were to be part of the result. Therefore, the discard of at least one of the specific prescriptions would form part of the calculation, before the result was given. (The prescriptions to be discarded might be chosen by some rule, or at random.) But then the result would be a conjunction of the remaining specific prescriptions and the prescription to act in defiance of the result. Again, at least one of the specific prescriptions would have to be discarded, in order to achieve the optimal result while still keeping the prescription to defy as part of that result, and this too would have to form part of the calculation. We would continue until only the prescription to act in defiance of the result was left. But as already noted, that would lead to incoherence.

We may therefore conclude that while the prescription to act in defiance of the result could be included in S, contrary to what Dostoevsky asserted, it could not coherently feature in a prescription of what to do in order to maximize advantage, so its inclusion in S would be idle.