system
Given the following post, respond as if you're commenting on Reddit:
human
Why can't we make ourselves fall asleep?

Clearly we can administer drugs to force ourselves to fall asleep, but is there any evolutionary reason why it would be disadvantageous to be able to intentionally sleep, or is there some physiological reason why it would be impossible?
gpt
Is there any reason why it would be evolutionarily ADVANTAGEOUS to intentionally sleep?

Our circadian rhythms are pretty well suited to the conditions we evolved in, where we would have easily gone to sleep around dusk and naturally woken around dawn. 

There wouldn't have been the kinds of distractions or pervasive sleep deficits we experience today, and thus the system worked perfectly well. No reason to adapt otherwise.