The traditional disputes of philosophers are, for the most part, as unwarranted as they are unfruitful - A. J. Ayer

I am using the word "perceive". I am using it here in such a way that to say of an object that it is perceived does not entail saying that it exists in any sense at all. And this is a perfectly correct and familiar usage of the word. If there is thought to be a difficulty here, it is perhaps because there is also a correct and familiar usage of the word "perceive", in which to say of an object that it is perceived does carry the implication that it exists.

... when one buys a pair of shoes, one is buying three things, the right shoe, the left shoe and the pair.

The ground for taking ignorance to be restrictive of freedom is that it causes people to make choices which they would not have made if they had seen what the realization of their choices involved.