Before G.E. Moore or Wittgenstein, he pointed out the leftness of a free-floating left hand to rebut "dogmatism" about absolute space, arguing instead that space and time are "forms of pure intuition" within the mind along with twelve (*) "categories of the understanding".
This philospher referred to the consistent conjunction of virtue and happiness using Cicero's term summum bonum, or highest good. Before G.E. Moore or Wittgenstein, he pointed out the leftness of a free-floating left hand to rebut "dogmatism" about absolute space, arguing instead that space and time are "forms of pure intuition" within the mind along with twelve (*) "categories of the understanding". In his attempt at a "Copernican revolution in metaphysics," this transcendental idealist argues that statements such as "7+5=12" can be deduced from simpler propositions without any empirical experience, showing that synthetic a priori truths are possible. FTP, name this Prussian Enlightenment-era philosopher who wrote Critique of Pure Reason. 
This philospher referred to the consistent conjunction of virtue and happiness using Cicero's term summum bonum, or highest good.
Immanuel Kant