Bertrand Russell, at his Nobel Prize Acceptance Speech, pointed out that all human activity is prompted by desire. If you want to know what man will do, you must know the whole system of their desires with their relative strengths.

Humans have some infinite desire...

Needs are limited. Desires are endless. Accepting the essential futility of trying to fulfill every desire we have is much wiser than indulging all of our impulses for gratification. 

Decide what your highest priorities are and focus on them and cut off other options.

These internal, psychological experiences exist on an inverted curve because they are both the cause and the effect of the same thing: our minds. When you desire happiness, your mind is simultaneously the thing that is desiring and the target of its own desires. 

The goal is to tak...