the same problem the gemoroh has regarding killing lice on shabboth applies to rambam
both gemoroh and rambam agree that animals and insects can come out of the body
and rambam sites aristotle for this because aristotle lived in the same time as the tannoim i think
and everyone back the believed that animals and plants can sprout from the body or ground
and rambam said that you would have to be an idiot not to believe it
well i am not an idiot and i dont believe it
because science proves its not so