That is to say, the fourth class of ideas given in the Essay on the Principle of Sufficient Reason must be the key to the knowledge of the inner nature of the first class, and by means of the law of motivation I must come to understand the inner meaning of the law of causation. Spinoza (Epist.
Horrek esan nahi du tratatuan ezarritako errepresentazioen laugarren klaseak giltza izan behar duela niretzat lehen klasearen barneko esentziaren ezagutzarako, eta motibazioaren legetik kausalitatearen legea ulertzen ikasi behar dudala, barreneko bere esanguraren arabera.