nihilism

nihilism is the view that certain things people often assume are “real” or “given”—like objective meaning, objective values, or a purpose built into the universe—may not exist. …

The key practical point is this: a claim about what exists in the universe is not the same as a recommendation about how to live. “There is no objective meaning” is descriptive. “Therefore I should act cruelly” is prescriptive.

J. Colle, Ardenne. Nihilism Explained: A Short Philosophy Book for Beginners on Existential and Moral Nihilism and the Meaning of Life, 13 & 21