"... that it is not from the value ...."

… that it is not from the value or worth of the object, which any person pursues, that we can determine his enjoyment; but merely from the passion with which he pursues it, and the success which he meets with in his pursuit. Objects have absolutely no worth or value in themselves.  They derive their worth merely from the passion.  If that be strong, and steady, and successful, the person is happy.

David Hume