It has been speculated, by Chomsky and others, that our capacity for scientific understanding is not only enabled but also limited by a biologically endowed science forming faculty (SFF). I look at two sorts of consideration for the SFF thesis and find both wanting. Firstly, it has been claimed that a problem-mystery distinction militates for the SFF thesis. I suggest that the distinction can be coherently drawn for cases, but that the purported‘evidence’for even a fairly lose general demarcation of problems and mysteries is not best explained by a SFF. Secondly, I consider in detail a range of cognitive considerations for the SFF thesis and contend that it is at best moot whether science can be so construed as to make it feasible that it is a faculty competence.