I find it pretty hard to believe the symbol is 'interchangeable" when each part of the eye has a significant meaning.
This site explains it quite well:
www.aloha.net...
The EYE OF HORUS has a very specific meaning. The eye is represented as a figure with 6 parts. These 6 parts correspond to the six senses - Touch, Taste, Hearing, Thought, Sight, Smell. These are the 6 parts of the *eye*. The eye is the receptor of *input*. It has these six doors, to receive data. The construction of the eye follows very precise laws. The senses are ordered according to their importance. And according to how much energy must be *eaten* by the *eye* for an individual to receive a particular sensation. All of the sensory data input is *food*.



I laugh when I think of all the stress related illness and
loss of sleep due to conspiracies perpetuated by simple 
