Dispensable/Indispensable Attributes

Indispensable and dispensable attributes are akin to mediums that are, and are not, morphophoric.

Figure 4: Two projected dots.

Consider the following VISION example illustrating attributes of color and spatial position:

1. two spots are projected side by side, one yellow and the other red;
2. next, two spots are in same location but both orange (though dispensed with color, spatial position is preserved);
3. next original red and yellow spots are projected on top of each other--only a single orange spot is visible;

Spatial position is thus indispensable: by dispensing with position, original yellow and red dots are not distinguishable.