[Fredkc]

Nature is simplicity itself.

Nature builds upon continuity, and where it's been; with what's at hand.

There lies the beauty and simplicity of it.

the last number before 1 is 0
1 + 0 = 1
The last number in "where it's been" is 1
1 + 1 = 2
The last number in "where it's been" is 1
2 + 1 = 3
The last number in "where it's been" is 2
3 + 2 = 5
The last number in "where it's been" is 3
5 + 3 = 8
8 + 5 = 13
13 + 8 = 21