When you're out of willpower, you can call on stubbornness.

The line contrasts two kinds of inner force. “Willpower” suggests a deliberate, disciplined capacity to choose the hard thing; “stubbornness” suggests a more instinctive, even irrational refusal to quit. Read this way, the quote argues that creative or personal endurance doesn’t rely solely on calm self-command: when rational resolve is depleted, sheer tenacity—an obstinate commitment to continue—can carry a person through fatigue, doubt, or resistance. Attributed to Matisse, it fits a common narrative about artists persisting through blocks and setbacks, implying that persistence can be powered by temperament as much as by virtue.