There has been a growth in the attempt to apply knowledge about the brain to philosophical problems, much of which is reductive in intent, and involves a category error. Nonetheless it is possible for knowledge of the brain to illuminate aspects of the phenomenal world in which we, as human persons, live. The nature of the attention we pay to the world changes what we find there, and it appears from research into the brains of birds, animals and humans that with the two cerebral hemispheres they pay quite distinct types of attention to the world. At the human level, this has predictable consequences for the nature of the world as experienced that each hemisphere brings into being for us. Each of these 'takes' on the world has its uses, and each needs to be taken into account. Knowledge of the way in which the brain functions cannot in itself answer questions about the ultimate nature of reality, but it can illuminate the problems we may encounter in trying to reach an understanding of the world. We also know that individuals can privilege one or other of these ways of bringing the world into being, such that they tend to perceive things in the world, approach the resolution of problems in the world, and conceive of themselves and their world, in a way which suggests a bias towards the view subtended by the functioning of one hemisphere only. Such a view can become the prevailing view of a culture, with important consequences.