A person is open-minded if…

I think a person is open-minded about some issue if she identifies her assumptions and opinions about the issue and is willing to subject her assumptions and her opinions to critical inquiry.

Gregory Ganssle, from Thinking About God: First Steps in Philosophy, p. 36

Once our minds are open…

Once our minds are open to open-mindedness, all ideas, no matter how absurd, can come and go as they please—with our sanction. We thus become headless and brainless philosophers who just want to get along.

Burk Parsons, from ‘Don’t Be So Open-Minded’ in Tabletalk, June 2008