Knowledge is like money: the more he gets, the more he craves.

The comparison treats knowledge not as a finite possession that brings contentment, but as something that intensifies desire. Like money, learning can be self-reinforcing: each new acquisition reveals further gaps, possibilities, and ambitions, making the seeker hungrier. Billings’s humor carries an edge of caution—intellectual accumulation can resemble material accumulation, driven by craving rather than wisdom or virtue. At the same time, the line can be read positively: curiosity grows with exposure, and the “craving” for knowledge is a sign of an active mind. The ambiguity—vice-like appetite or healthy curiosity—gives the aphorism its staying power.