ignorance and bias

Total ignorance is often represented as a uniform probability distribution over all possible states of nature. (Strictly speaking, even this is not total ignorance since you at least know what all the possible states are.)

Can ignorance have a non-uniform form?

There can be two reasons why I believe that an event is more likely to happen than another:

(i) I am drawing on from some previous knowledge, meaning that I am biased. In other words, I am not in a state of total ignorance.

(ii) There are some physical constraints that shape the context of the event. For example, the final position of a cannon ball is a function of the direction of the cannon and the shape of the landscape. Even if the cannon is uniformly likely to shoot in any direction, the final position is not uniformly distributed across the landscape. In this case, the deviation from the uniform probability distribution has an outside (physical) origin.

So ignorance is always uniform from within, but its manifestation can be non-uniform due to external physical factors. (Hence the Bayesian interpretation of quantum physics is wrong.)