 Carnap, Rudolf |  Dedekind, Richard: contributions to the foundations of mathematics |  descriptions |  law: and language | logical atomism |  Moore, George Edward |  neutral monism |  Principia Mathematica: notation in |  propositional function |  propositions |  Quine, Willard Van Orman |  Russell, Bertrand |  Russell’s paradox |  set theory |  structural realism 