To use the same words is not a sufficient guarantee of understanding; one must use the same words for the same... — Friedrich Nietzsche

To use the same words is not a sufficient guarantee of understanding; one must use the same words for the same genus of inward experience; ultimately one must have one's experiences in common.

Author: Friedrich Nietzsche

Insight: We often assume that if two people use the same word, they're talking about the same thing. A friend says they're "tired" and you nod like you get it—but maybe they mean physically exhausted, while you're thinking emotionally drained. The word creates an illusion of connection that might not actually exist. Nietzsche's point cuts deeper than just vocabulary. He's saying that real understanding requires something almost impossible to verify: that the word comes from the same lived experience, the same kind of body and history and feeling. When someone who's never been lonely talks about loneliness, or someone who's never risked anything talks about courage, the words are just noise. This is why certain people can explain something in ten seconds and you suddenly get it, while experts can talk for hours and leave you cold—it's not always about clarity, but about whether their experience mirrors something in yours. The unsettling part is that this means some gaps can never fully close. We can build empathy, but we can't truly crawl into another person's inward experience. What we can do is stay honest about that gap, and be suspicious of easy agreement. Real understanding is rarer than we pretend.

Source: The Genealogy of Morals, Essay I, Section 11, 1887