Mathematicians decided early on that strict rules must be imposed on mathematical proofs otherwise we may have a proof that does not match with the actual truth. The four color theorem is believed to be proven by some, but the proof was done by exhaustion using computers. It is debated whether this proof holds up to the standards. We may have yet to prove the proofs of the six color theorem and even the five color theorem. These theorems stating that you do not need more than five or six colors.