ABSTRACT
These conditions are logically independent of each other in that, for a given specification of a material object array, any one of the three conditions can be satisfied without either of the other two being satisfied and any two can be satisfied without the third being satisfied. For example, think of a case in which you are looking at what you know very well to be a solid object – say a bush – standing in front of a wall; but for a moment it looks to you just like, you see it as, something drawn on the surface of the wall. Then, for one specification of an M-array, we have the first two conditions satisfied without the third; and for another specification we have the third condition satisfied without the other two.
