Religion is the masterpiece of the art of animal training, for it trains people as to how they shall think.

The remark expresses Schopenhauer’s characteristically polemical view that organized religion functions less as a path to truth than as a mechanism of social control. By calling it a “masterpiece” of “animal training,” he reduces human beings to creatures whose beliefs can be conditioned through repetition, authority, and reward/punishment structures. The emphasis on training people “how they shall think” targets doctrine and orthodoxy: religion, on this reading, supplies ready-made metaphysical answers and moral directives that pre-empt independent inquiry. The quote also fits Schopenhauer’s broader suspicion of institutions that exploit fear and hope—especially regarding death—to shape conduct and maintain order.