Everyone should learn to do one thing supremely well because he likes it, and one thing supremely well because he detests it.

The saying urges a twofold discipline: cultivate excellence in a chosen pursuit that genuinely attracts you, and also master at least one necessary task you would rather avoid. Read this way, it balances vocation with duty—pleasure-driven skill builds identity and joy, while competence in disliked work builds resilience, self-reliance, and freedom from dependence on others. The contrast (“likes” vs. “detests”) also implies that character is formed not only by talents we enjoy exercising but by the habits we develop when confronting drudgery. In a frontier or communal setting, the idea fits a practical ethic: communities thrive when individuals both contribute their gifts and can shoulder unglamorous labor.