What am I? What I am.

"The primary color between green and orange in the visible spectrum, an effect of light with a wavelength between 570 and 590 nm." - Dictionary.com

"...Appears to be a primary or simple colour, but in fact it is signalled at the retina by a mixture of red-and green-sensitive (cone) receptors having overlapping spectral sensitivity. This is a warning that it is not possible to infer the simplicity of physiological mechanisms from the simplicity or apparent complexity of experience. It shows indeed the fallibility of introspection for understanding functions of the nervous system, if not of the mind."  
- Answers.com

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No need to even guess.