Penetrating so many secrets, we cease to believe in the unknowable. But there it sits nevertheless, calmly licking its chops.
-- H. L. Mencken
\begin{bmatrix} 1 & 0 & \ldots & 0 \\
0 & 1 & 0 & \vdots \\
\vdots & 0 & \ddots & 0\\
0 & \ldots & 0 & 1_{n}
\end{bmatrix}