My text looks critically at some huge gaps in our scientific knowledge. I often suggest observations which might be made or directions in which research might go. As a retired chemical researcher, I am discomfited by the many things we do not know. (Thus I applaud the great success of atomic theory in accounting for the properties and behaviour of so many substances. Yet cosmologists, as I explain in Chapter 2, now feel that much of the universe is not atomic at all, but ‘dark matter’. Where and what is it? My inexpert guess is that if it exists, it does so as dense clumps or nuclei in the centres of stars or planets, so that surface creatures like ourselves never come across it. We only encounter atomic matter and have built our chemistry around it. So chemistry, like much of science, has huge gaps in it). In this book I point out some of the desperate gaps in modern science. My basic one is incontestable, and I simply explore it as a huge anomaly. Why are we conscious? Consciousness is the only thing we are directly aware of; yet there is no theory of it. Modern 220biochemistry claims that we are all made entirely of atoms. Nothing made of atoms should be conscious: but we are. Nobody understands how a brain can be conscious. Attempts to make a conscious computer have so far not been successful. I extend the puzzle of consciousness by invoking one of the most important hypothesis of the 1900s: the unconscious mind. It is a common psychiatric assumption that we all have one. Indeed, psychiatrists often claim to have recovered some memory or personal characteristic that has been ‘repressed’ into it. Nobody has any way of exploring it—introspection, of course, simply allows you to scan your conscious mind. The contents and size of the unconscious mind are simply not known. One biological theory is that the higher animals have unconscious minds as well. Since they seem to be conscious too, I tie these ideas together. I make the bold claim that in order to be conscious at all, you need an unconscious mind. This does not explain consciousness, that strange property of a few specialized systems of atoms, but it fits smoothly into evolution theory. Evolution does away with sharp transitions, which may have contributed to its opposition by theology. Theology requires a sharp transition: an animal ape has offspring which are human. By contrast, evolution supposes that certain apes evolved smoothly into mankind. Given that they already had unconscious minds, and were already conscious, the evolutionary process merely requires that (among other changes) their brains, voice boxes and hands greatly improved their functioning.