|From RZA's The Tao of Wu|
Well, the Buddha didn't say "all is illusion," but I still like this! The Buddha said everything is impermanent and the belief in solidity or fixity is an illusion -- and the cause of suffering. The notion of the world as illusion is more of a Hindu thing, associated with Advaita Vedanta. The idea is that the physical world obscures the ultimate reality, and the ground of all being, Brahman.