There are many explanations of karma within Buddhism and it is the most difficult topic according to the Buddha himself. However, we can say that it is not deterministic, because it is possible to change what we experience; it’s possible to change what we do. And it’s not predetermined, because predetermination would imply that there is somebody external to the system who has decided what’s going to happen. It’s not total free will, which would imply that there is a “me” who is totally independent of everything, making a choice of what to do lfrom a menu. Rather, whatever we experience can be explained – there are causes.