Purple is the color of kings.
Despite this 'royal' association, in the democracy of the Color Wheel the color purple is seated right amongst all the other colors ... between red and blue, to be precise.
Purple comes in warm, reddish, more 'passionate' hues and in cooler, complex plum and indigo ones.
Yellow is often described as an optimistic, life-affirming color that reminds us of sunshine and stimulates our mind, body and emotions.
Some people also find that it helps them with concentration.
The effect of the color yellow obviously varies with its intensity and hue.
A pale, atmospheric tint of yellow on walls or ceiling can add 'sunshine' to a room, while saturated, intense yellows might make you feel cranky after a while.
The color orange is generally experienced as the warmest color.
Between yellow and red on the Color Wheel the psychological effects of the color orange seem to combine those of red and yellow.
Orange is a sensuous color. It is perceived as emotionally stimulating, energetic, vibrant and fun.
The psychological effects of the color blue are probably universal. Almost everyone enjoys looking into a blue sky and across a lake or the sea. There is something calming about an expanse of blue. It appears to free the mind. In interior decorating, you can use the color blue to create a reflective, 'intellectual' atmosphere: it's not easy to overheat emotionally and get upset or aggressive in a 'cool' environment