Sraffa and Wittgenstein influenced each other deeply. They continually corresponded and discussed each other in their journals and notebooks. Both authors were dealing with a form of positivism dominant in their respective disciplines, economics and philosophy. While Wittgenstein made his famous turn from the Tractatus Logico-Philosophicus to the Philosophical Investigations wherein he jettisoned the previous idea that the world comprised an atomistic set of propositional facts for the notion that meaning derives from its use within a holistic self-enclosed system. Analogously, Sraffa was rebutting the Neoclassical paradigm which was similarly atomistic, individualistic and derivational (see Criticisms of neoclassical economics). While there are disputes about how to interpret Sraffa—falling primarily into the neo-classical camp of Paul Samuelson and the Neo-Ricardian of Pierangelo Garegnani—none dispute Sraffa's influence and it can be argued that Sraffa's critique of neo-classical economics is analogous to that of Wittgenstein's of philosophy, in that Sraffa sought to replace the individualistic and positivistic account of price as the result of an equilibration of supply and demand, for instead as price serving a social function, namely to reproduce a stationary or expanding economy given a distribution of income.