Monthly Archives: May 2015

The Truth of One Plus One Equals Two

Postcard Grand Central Station New York NYIf I wander into a crowded train station and scream “One plus one equals two!” at the top of my lungs, or mutter it to myself, and there is no apparent pair I am gathering together, are my words true?  Are they true even if they do not connect with anything or do anything for anyone?  If we say they are true in the abstract, is that true in a particular context, or in all contexts?

Principia_Mathematica_proof that one plus one equals twoIf Bertrand Russell and Alfred North Whitehead spent over 350 pages in the Principia Mathematica (1910) to prove, with absolute certainty via logic, that one and one make two, was it just as true as it was before?  Is it now more certain?  How certain are children, compared to Russell’s readers?