ABSTRACT
We live in the illusionary world of our subjective and cultural beliefs rather than really knowing the objective world directly. It is important to understand the limitations of our biological brain so we can know what it can and cannot do, and how reliable it is when it comes to creating knowledge. Our natural irrationality is at root caused by automatic decisions made by the primitive parts of our brain. The other, more sophisticated parts of the brain use conscious, critical thinking to weigh evidence and use judgment in order to form more accurate beliefs and take deliberate action. But this kind of critical thinking requires a lot of energy and effort, so it is often impractical for many everyday decisions.
