Bad Maths

We taught him wrong,

$$\begin{aligned} &e^{i \cdot Pi}=-1 \\ &e^{i \cdot P \cdot i}=-1 \\ &e^{P \cdot {i \cdot i}}=-1 \\ &e^{P\left(i^{2}\right)}=-1 \\ &e^{-P}=-1 \\&e^{-2 P}=1 \\ &P=0 \rightarrow \boxed{\therefore P=N P} \end{aligned}$$