Differential programming is about building software that is differentiable end-to-end, so that optimal solutions can be calculated with gradient descent.
Probabilistic programming (which is a bit more vague) is about specifying probabilistic models in an elegant and consistent way (which than then be used for training and inference.)
So, you can build some kinds of probabilistic programs with differential programming languages, but not vice versa.
Differential programming is about building software that is differentiable end-to-end, so that optimal solutions can be calculated with gradient descent.
Probabilistic programming (which is a bit more vague) is about specifying probabilistic models in an elegant and consistent way (which than then be used for training and inference.)
So, you can build some kinds of probabilistic programs with differential programming languages, but not vice versa.