„Pure Mathematics is the class of all propositions of the form “p implies q,” where p and q are propositions containing one or more variables, the same in the two propositions, and neither p nor q contains any constants except logical constants. And logical constants are all notions definable in terms of the following: Implication, the relation of a term to a class of which it is a member, the notion of such that, the notion of relation, and such further notions as may be involved in the general notion of propositions of the above form. In addition to these, mathematics uses a notion which is not a constituent of the propositions which it considers, namely the notion of truth.“

Principles of Mathematics (1903), Ch. I: Definition of Pure Mathematics, p. 3
1900s

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Bertrand Russell foto
Bertrand Russell45
logik a jeden z prvních analytických filozofů 1872 - 1970

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Kontext: Social positivism only accepts duties, for all and towards all. Its constant social viewpoint cannot include any notion of rights, for such notion always rests on individuality. We are born under a load of obligations of every kind, to our predecessors, to our successors, to our contemporaries. These obligations then increase or accumulate, for it is some time before we can return any service. … Any human right is therefore as absurd as immoral. Since there are no divine rights anymore, this concept must therefore disappear completely as related only to the preliminary regime and totally inconsistent with the final state where there are only duties based on functions.

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