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WW

HEADERS_END

A recurring theme in mathematics is that sometimes

different things have something in common. Finding

that something and then studying it in isolation,

in the abstract, can then teach us something about

everything.

If you see what I mean.

A case in point is an area of mathematics called

Group Theory. There are many cases where we have

a collection of things, along with some way of

combining them. Examples are numbers (which we

combining them in specific way are classified as groups. Examples are numbers (which we

can add or subtract) and rotations (which we can

combine by doing one after the other).

Galois did a lot with group theory, to the point

where there's a sub-topic call Galois Theory.