“Christianity is a life, not a doctrine . . . I'm not saying never doubt or question. The Lord gave you a mind so that you would make honest use of it. I'm saying you must be sure that the doubts and questions are your own.”

“The Lord gave you a mind so that you can make honest use of it. I'm saying you must be sure that the doubts and questions are your own, not, so to speak, the mustache and walking stick that happen to be the fashion of any particular moment.”

“I am saying you must be sure that the doubts and questions are your own, not, so to speak, the mustache and walking stick that happen to be the fashion of any particular moment”

“Be honest: did you actually read [the above geometric proof]? Of course not. Who would want to? The effect of such a production being made over something so simple is to make people doubt their own intuition. Calling into question the obvious by insisting that it be 'rigorously proved' ... is to say to a student 'Your feelings and ideas are suspect. You need to think and speak our way.”

“The more you believe, the more you doubt. The more you doubt, the more you ask questions. Knowing that questions left unanswered is the best proof for your belief.”

“Does it never strike you that doubt can be a madness, as well as faith? That asking questions may be a disease, as well as proclaiming doctrines? You talk of religious mania! Is there no such thing as irreligious mania?”