Answer:
The more you take, the more you leave behind.
Always old, sometimes new. Never sad, sometimes blue. Never empty, sometimes full. Never pushes, always pulls.
I sleep by day, I fly by night. I have no feathers to aid my flight.
I run around the city, but I never move.
They make no sense at all, In them you either fly or fall. They make you do it all. Their need is biologic, but they are most illogic. They are not real but still can be achieved, If they are just believed
You use it between your head and your toes, the more it works the thinner it grows.