This article draws attention to a generalizable phenomenon called “transforming poison into medicine,” illustrating both literal and figurative applications. The purpose of such illustrations is to support a strong philosophical claim, namely the currently incomplete reduction (if not the ultimate irreducibility) of intentional mind-states – e.g., beliefs, desires, volitions – to electro-chemical brain-states. Such incomplete reduction (or irreducibility) holds profound implications for the ineluctable role of dualism in neuroscience and psychiatry alike.