However, Saul Kripke argued compellingly against the descriptivist theory. Kripke attributes variants of descriptivist theories to Frege, Russell, Wittgenstein and John Searle, among others. Hilary Putnam rejects descriptivist approaches to natural kinds with semantic reasoning. In his book "Naming and Necessity", Saul Kripke criticised the descriptivist theory. Kripke sets out what he believes to be the tenets of the descriptivist theory. Kripke thinks that this is a phenomenon that the descriptivist cannot explain. This is known as the descriptivist theory of names. Central to his previous lectures was his attack on the descriptivist theory of reference. This is far too counter-intuitive for the descriptivist theory to hold.