1. Air (Yellow) represents mind and thoughts, the ability to think.
2. Water (Blue) represents emotions.
3. Fire (Red) represents will, the ability to direct your thoughts and emotions towards action on the physical plane.
4. Earth (Green) represents all the materials on the physical plane that the three subtle-elements interact with.
5. Space (White), or aether, represent the "5th element" and it is the "background canvas" or "cosmic lattice" that the "material earth" is projected upon.
While I believe that the "five elements" actually related to a funamental truth about the structure of matter at the microcosmic level, I also really like how in alchemy they're used as a metaphor for the ingredients of human experience.
