Question

For an external observer (say, an alien), is it correct for him to assume that there is no free choice?
First of all, why should he think about free choice at all? And if he already did think about it, then according to Occam's razor a mechanistic explanation is obviously preferable to adding some unfamiliar, fundamental force that cannot be explained.
(As human beings, of course, one can argue from subjective experience, and maybe aliens can factor that into their calculations. Maybe they could also arrive at the conclusion that the Torah is true, and therefore that there is free choice. But I want to understand whether, at base, one should indeed assume determinism.)