I believe there is no source of deception in the investigation of nature which can compare with a fixed belief that certain kinds of phenomena are impossible.

More from William James

• A great many people think they are thinking when they are merely rearranging their prejudices.
• Genius in truth means little more than the faculty of perceiving in an unhabitual way.
• The community stagnates without the impulse of the individual. The impulse dies away without the sympathy of the community.