I'm a retarded undergrad, but I'm trying to see how to get from the Lagrangian of a Dirac field to the Dirac function. This is literally brainlet tier stuff, but I can't understand why the derivative of the adjoint operator, $\frac{d}{d\psi}\overline{\psi}=0.$ Or alternatively, as in pic related, $\frac{d}{d\overline{psi}}\psi=0.$
By the way, $\overline{psi}=\psi^{\dagger}\gamma^0.$
In the off chance someone on here isn't retarded, could you please explain why this is?