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Single Idea 17627

[filed under theme 6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics ]

Full Idea

It is an apparent absurdity in proceeding ...through many rather recondite propositions of symbolic logic, to the 'proof' of such truisms as 2+2=4: for it is plain that the conclusion is more certain than the premises, and the supposed proof seems futile.

Gist of Idea

It seems absurd to prove 2+2=4, where the conclusion is more certain than premises

Source

Bertrand Russell (Regressive Method for Premises in Mathematics [1907], p.272)

Book Ref

Russell,Bertrand: 'Essays in Analysis', ed/tr. Lackey,Douglas [George Braziller 1973], p.272


A Reaction

Famously, 'Principia Mathematica' proved this fact at enormous length. I wonder if this thought led Moore to his common sense view of his own hand - the conclusion being better than the sceptical arguments?


The 7 ideas with the same theme [establishing new certainties from a starting point]:

To decide some questions, we must study the essence of mathematical proof itself [Hilbert]
It seems absurd to prove 2+2=4, where the conclusion is more certain than premises [Russell]
For intuitionists, proof is inherently informal [Shapiro]
There is no limit to how many ways something can be proved in mathematics [Brown,JR]
Computers played an essential role in proving the four-colour theorem of maps [Brown,JR]
Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall]
Computer proofs don't provide explanations [Horsten]