Well, according to accepted style, yes. Conjunctions and prepositions are lower case in titles. The Life of an Elephant would be more widely accepted, unless of course the author titled it in all uppercase, in which case you would follow the author’s convention.
Mmm. The concept that a bunch of minds can occupy a shared mental space?
Fictional and unlikely to happen soon.
The idea that human interactions and perceptions can happen dozens or thousands of times faster by constructing a dream-within-a-dream-within-a-dream-within-a-dream?
Pretty neat for a midnight dorm room conversation, but baseless and almost certainly physiologically impossible.
The idea that a bunch of people would kidnap an extremely rich-powerful person in order to hop into his mind to try some nebulous pop psychology manipulations?
The big reason I hated the movie.