For real?

When Dr.Carmus meets Alan he explains to him how the senses or the soul of
those who died can survive physical death as ghosts.
He tries to illustrate this in the film by decapitating a live snake.
He shows how the snake's head even after decapitation can still manage to move/respond to stimuli.
But to jump from that and prove conclusively that one's spirit or desires can
somehow survive years later as a ghost is a real far jump.

Surely if he really was a man of science he couldn't make such a conclusion
based on the reflexive actions of a decapitated snake.
This has got to be the textbook definition of the word "ridiculous".
But of course this is only a movie so you can't expect everything to make
total sense right?

Maybe this world is another planet's Hell. - Aldous Huxley (1894-1963)