Arjuna falls a Materialist and rises an Idealist; that’s the Bhagavad Gita in eight words. A Materialist is someone who believes the universe is made of stuff and does, in truth, exist. An Idealist believes the universe is made of thought and does not, in truth, exist. In other words, the former believes that reality is real, and the latter once did, but has been disabused of their error. We’re all either hardcore Materialists or hybrid Materialist-Idealists. If someone claims to be a straight-up Idealist, just flush the can when they’re in the shower and they’ll sing a different tune.