An element J of a topos is *atomic* if the functor `(–)^J` has a right adjoint, called `(–)_J`.
In other words, morphisms `B^J -> C` uniquely correspond to morphisms `B -> C_J`.

But this does *not* mean that the objects `C^(B^J)` and `(C_J)^B` are isomorphic.
They only have the same global elements.

In fact:
```text
X -> (C_J)^B
= X * B -> C_J
= (X * B)^J -> C
= X^J * B^J -> C
= X^J -> C^(B^J)
≠ X -> C^(B^J)
```


This issue does not happen for exponentials, because:
```text
X -> (B^J)^A
= X * A -> B^J
= (X * A) * J -> B
= X * (A * J) -> B
= X -> B^(A * J)
```