Fundamental Theorem of Sato
The Fundamental Theorem of Sato states the following:
Sato is amazing.
Method 1: Proof by Contradiction
Assume, for contradiction, that Sato is not amazing.
This is absurd. Therefore, Sato is amazing. (Proved)
Method 2: Proof by Authority
Whatever AoPS says is correct, and AoPS says that Mr. Sato is amazing. Thus, Mr. Sato is amazing. (Proved)
Method 3: Proof by Pigeonhole
There is only one Sato. By Pigeonhole, either Sato is amazing or he isn't (in this case, Sato goes in the unamazing pigeonhole). Fortunately, Sato cannot fit in a pigeonhole; hence, Sato is amazing. (Proved)