He believed the universe doesn’t give us a grand purpose, and that searching for one might drive us crazy (The Myth of Sisyphus). But instead of giving up, Camus says we should embrace life, rebel against meaninglessness, and create our own purpose.
You’re pushing a boulder up a hill forever, and there’s no ultimate prize at the top. Instead of despairing, Camus says, smile and keep pushing—find joy in the struggle itself. That’s existential defiance.