CATS shows that mathematics is simple if respecting its nature as a natural science about MANY.
To deal with MANY we simply count and add, as demonstrated when writing a Total as we say it:

T = 456 = 4*10^2 + 5*10 + 6*1.

This shows why algebra means re-unite in Arabic:
We count MANY by uniting the ones in bundles, in this case ten-bundles, ten-bundles of ten-bundles etc.

Also we see that

• All numbers carry units: ones, tens, ten-tens etc.
• There is 4 ways to add: +, *, ^, integration, where

+ adds unlike numbers,
* adds like numbers,
^ adds like factors
  integration adds stacks with different units next-to each other as areas.

Thus, adding next-to roots integration, adding on-top roots linearity forcing totals to be recounted in the same unit, and reversing addition roots equations.

Mathematics is as simple as that, when introduced as a natural science about MANY by CATS.

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