Analysis of Wistful Thoughts

Oh! What a creation is man,
behold the sinew under skin,
the flex of muscle, the glimmer of eye,
the noble posture, the keen wit.
But why is it so? Not always was it thus,
from Neolithic caveman, primitive and bare,
through Nile's rich valley, and Athens' awe
man lived and lives in peace and bloody war.
Full circle will he travel, and through
the aeons pass to his past self become.