Nagel began to publish philosophy at the age of twenty-two; his career now spans over fifty years of publication. Nagel thinks that each person, owing to his or her capacity to reason, instinctively seeks a unified world view. However, if this aspiration leads one to believe that there is only one way to understand our intellectual commitments, whether about the external world, knowledge, or what our practical and moral reasons ought to be, this leads one into error. For contingent, limited and finite creatures, no such unified world view is possible. That is because ways of understanding are not always better when they are more objective.