Are sensations real? That is, do they continue to exist when unperceived? It seems to me that objects that I perceive around me are both real (because outside my head) and composed of sensations: that is, they are structures of colours, tactile qualities, etc.; in which case these sensatations, as parts of real objects, are real. But it also seems obvious that sensations exist only while perceived, in which case they are not real.