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So, in 1910, prominent mathematicians and philosophers Bertrand Russell and Alfred North Whitehead

published a book. And that book was called Principa Mathematica.

And this book was their attempt to answer a seemingly innocuous question.

Why is it that 1 plus 1 equals 2? And to hear that that question for someone with a very base level understanding of mathematics might sound quite silly.

It may even sound too obvious to be asking seriously, especially as a prominent mathematician.

But in asking this question and seriously attempting to answer it,

Russell and Whitehead are tapping into something about not just numbers, but mathematics, that is quite mysterious.

And that is the fact that in actuality we very much take these concepts such as

one or two or three or even add or equals,

very much for granted.

I think when we all first begin to learn maths,

well, one plus one, equaling two,

is perhaps one of the first things that we learn.

It is foundational to the idea of mathematics.

And further still, I think that there might be something rather intuitive about the idea to people.

It's easy to picture taking one thing, adding another thing, and calling those two things combined, too.

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