While we may not all feel the effects of colour quite so literally as Picasso, it can undoubtedly both influence and reflect our moods. In turn, our perceptions, decisions, and actions are all influenced by our emotions. But our response to colour is complex and personal. Each of us will have our own unique perception of colour. Is the red I see the same as the red you see? How can we know for sure? Why does one person love a certain shade of green, when for someone else that particular colour seems hideous?