Freudian psychology interpreted daydreaming as expression of the repressed instincts similarly to those revealing themselves in nighttime dreams. Like nighttime dreams, daydreams, also, are an example of wish-fulfillment (based on infantile experiences), and are allowed to surface because of relaxed censorship. He pointed out that, in contrast to nighttime dreams, which are often confusing and incoherent, there seems to be a process of "secondary revision" in fantasies that makes them more lucid, like daydreaming. The state of daydreaming is a kind of liminal state between waking (with the ability to think rationally and logically) and sleeping. They stand in much the same relation to the childhood memories from which they are derived as do some of the Baroque palaces of Rome to the ancient ruins whose pavements and columns have provided the material for the more recent structures.