Again, the desires arising from the emotions whereby we are assailed are stronger, in proportion as the said emotions are more vehement; wherefore their force and increase must be defined solely by the power of external causes, which, when compared with our own power, indefinitely surpass it (IV.
Gainera, josten gaituzten afektuetarik sortzen dira Desirak; zenbat eta sutsuago baitira afektu horiek, hainbat eta handiago ere Desirak; eta, beraz, hauen indarra eta hazkundea (5. Prop. arab.) kanpoko kausen ahalmenaren arabera definitu behar da; ahalmen horrek, gurearekin konparatuz geroz, mugarik gabe gainditzen duelarik gurea (3. Prop.