Deliberation under determinism
We often deliberate before making decisions: we consider reasons for and against different options before choosing one. Good thing too. It would be silly if we always just tossed a coin instead. But some philosophers claim that you can’t deliberate in good faith if you accept determinism. They say that you can’t deliberate rationally and sincerely unless you believe that the prior conditions leave open more than one option, contrary to determinism. To deliberate rationally and sincerely about whether (say) you’ll accept or decline an invitation, you must believe that the prior conditions haven’t already necessitated one of those options.
Other philosophers, including me, disagree. Look more carefully, we say, and you’ll see that what rational and sincere deliberation requires is, instead, a state of ignorance: the inability to see how the prior conditions necessitate choosing a particular option or which option it is. Because the prior conditions are unfathomably complicated, we find ourselves in that state of ignorance all the time.
Crucially, you must also believe (at least tacitly) that your deliberation will make a difference to your decision: you must believe that your deliberation has a point. Determinism emphatically entitles you to that belief, because determinism says that the decision you end up making strictly depends on prior conditions that include any deliberation you engage in. Determinism absolutely does not say that you’ll make the same decision regardless of whether or how you deliberate.
You deliberate because you need to “make up your mind” about what to do. Determinism isn’t a shortcut that lets you make up your mind without the (sometimes hard) work of deliberating. Nor does determinism imply the obvious falsehood that you’ve already made up your mind before you deliberate. To state the obvious, you haven’t made up your mind until you have.
What rational and sincere deliberation requires is a state of ignorance that we occupy all the time and a belief in the efficacy of deliberating. Determinism accommodates both.
[For more details on this topic, see section 3.2 of my book and the literature cited there.]
