Renatus Cartesius has been dubbed the "Father of Modern Philosophy". Born on March 31, 1596, he gave us the well known philosophical statement ( Cogito ergo sum : I think, therefore I am). Renatus also is credited as the father of analytical geometry. Without the use of his system you will not be able to solve this puzzle.
x-3 y-3, x-3 y3, x3 y-3, x3 y3
x2 y3, x2 y-3, (x-3 y3, x-3 y0, x2 y0)
x-3 y3, x3 y3, x3 y0, x-3 y0, x-3 y-3, x3 y-3
x-3 y3, x3 y3, x3 y0, x-3 y0, x-3 y-3, x3 y-3
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3, (x-3 y0, x3 y0)
x2 y3, x2 y-3, (x-3 y3, x-3 y0, x2 y0)
x-3 y3, x3 y3, x3 y-3, x-3 y-3, (x-3 y0, x3 y0)
x-3 y3, x-3 y-3, x0 y3, x3 y-3, x3 y3
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3, (x-3 y0, x3 y0)
x-3 y-3, x3 y-3, x3 y3, x-3 y3, x-3 y0, x3 y0
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3
x-3 y3, x-3 y-3, x3 y-3, x3 y3, x-3 y3
x3 y3, x-3 y3, x-3 y-3, x3 y-3, x3 y0, x-3 y0
x-3 y3, x3 y3, x3 y0, x-3 y0, x-3 y-3, x3 y-3
x3 y3, x-3 y3, x-3 y0, x3 y0, x3 y-3, x-3 y-3
You can validate your puzzle solution with certitude.