Posted by Jerry on August 27, 2007
The other evening, I was thinking about the effect of illusions, for reasons not known to me. With the benefit of hindsight and historically amassed knowledge, I find it amusing that Descartes was so frustrated with the effects of illusions and its apparent invalidation of the senses as legitimate tools of perception. Everything–literally everything–was uncertain to him because it rested on our sense perceptions.
The point about illusions, however, is that it is as objectively real as any other perception. There’s nothing wrong with our eyes if we see a visual illusion, because the perception of an illusion occurs not at the point of sensory contact but at the cognitive level of perception in our brains. In other words, an illusion would not exist unless there are certain characteristics in the object as well as a certain mode of sensory perception by a conscious perceiver. Our senses do not deceive us in any way because the perception of an illusion is a trick of cognition occuring in response to the characteristics of the object being perceived.
For example, without the kind of eyes that we do have, we would not be able to cognitively perceive color–and color could be regarded as an all-pervasive illusion if you like to think of color as nothing more than different wavelengths of light. In other words, if the wavelengths of light did not exist, then color would not exist; but at the same time, if we didn’t have the kind of visual sense organs that we do have–or if we had faulty ones–then color (as we know it) would not exist either! This demonstrates the objectivity of illusions and the axiomatic quality of sensory perception.
I guess the philosophical point of this essay, then, is to emphasize that Objectivism is neither realism nor subjectivism; realism is mind-independent centric, or as Rand called it, intrinsicism, and we all know what subjectivism is.