Chapter 3 tackles some of the ‘hard’ problems with consciousness. First, it is impossible to imagine the relationship between consciousness and the invisible physical world. Second, we find it difficult to imagine the connection between conscious experiences of brain activity and other conscious experiences. Third, there are brute regularities between consciousness and the physical world that cannot be broken down or further explained. None of these problems are unique to consciousness research. They can also be found in physics, and they do not affect our ability to study consciousness scientifically. We can measure consciousness, measure the physical world and look for mathematical relationships between these measurements.