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Single Idea 6408

[filed under theme 6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism ]

Full Idea

In order to deduce the theorems of mathematics from purely logical axioms, Russell had to add three new axioms to those of standards logic, which were: the axiom of infinity, the axiom of choice, and the axiom of reducibility.

Gist of Idea

Russell needed three extra axioms to reduce maths to logic: infinity, choice and reducibility

Source

A.C. Grayling (Russell [1996], Ch.2)

Book Ref

Grayling,A.C.: 'Russell' [OUP 1996], p.31


A Reaction

The third one was adopted to avoid his 'barber' paradox, but many thinkers do not accept it. The interesting question is why anyone would 'accept' or 'reject' an axiom.


The 20 ideas from A.C. Grayling

It is legitimate to do harm if it is the unintended side-effect of an effort to achieve a good [Grayling]
War must also have a good chance of success, and be waged with moderation [Grayling]
Russell needed three extra axioms to reduce maths to logic: infinity, choice and reducibility [Grayling]
Two propositions might seem self-evident, but contradict one another [Grayling]
Majority decisions are only acceptable if the minority interests are not vital [Grayling]
Liberty and equality cannot be reconciled [Grayling]
The very concept of democracy entails a need for justice [Grayling]
There should be separate legislative, executive and judicial institutions [Grayling]
A cap on time of service would restrict party control and career ambitions [Grayling]
Experience, sympathy and history are sensible grounds for laying claim to rights [Grayling]
Politics is driven by power cliques [Grayling]
Democracies should require a supermajority for major questions [Grayling]
It is essential for democracy that voting is free and well informed [Grayling]
In an honour code shame is the supreme punishment, and revenge is a duty [Grayling]
In Greek mythology only heroes can go to heaven [Grayling]
Religion gives answers, comforts, creates social order, and panders to superstition [Grayling]
To make an afterlife appealing, this life has to be denigrated [Grayling]
Lucretius was rediscovered in 1417 [Grayling]
If suicide is lawful, but assisting suicide is unlawful, powerless people are denied their rights [Grayling]
The argument from analogy is not a strong inference, since the other being might be an actor or a robot [Grayling]