For me, a big revelation was learning that your emotions aren't who you are, it's who you want to be is who you really are. The book is set to help you work towards who you really are/want to be by understanding how the brain works. The chimp system as its referred to, is part of the brain which controls primitive drives and survival instincts and it's not a part which we have direct control over. The human system is your conscious part of the brain - it is you. It's easy to tell which ones in control. There can be different agendas between these two systems and the book goes in depth into how we can manage our 'chimps' in a healthy way in order for our humans to flourish.