"It either occurred or it did not occur"

"Our whole strength rests on the validity of that vision. It either occurred or it did not occur. If it did not, then this work is a fraud. If it did, then it is the most important and wonderful work under the heavens." ("The Marvelous Foundation of Our Faith", Gordon B. Hinckley Oct 2002)

"Inquiries from honest searchers after truth should always be welcomed. Intelligent learners, in any field of knowledge, ask for explanations as problems appear in their studies. Indeed, the questions asked often mark the degree of proficiency attained. Those to whom no problems occur are asleep at the wheel of truth."
(John A. Widtsoe, Evidences and Reconciliations, p. ix)

“The doctrine of the Church cannot be fully understood unless it is tested by mind and feelings, by intellect and emotions, by every power of the investigator. Every Church member is expected to understand the doctrine of the Church intelligently. There is no place in the Church for blind adherence.”
~John A. Widtsoe, Evidence and Reconciliations, p. 226

“The man who cannot listen to an argument which opposes his views either has a weak position or is a weak defender of it. No opinion that cannot stand discussion or criticism is worth holding. And it has been wisely said that the man who knows only half of any question is worse off than the man who knows nothing of it. He is not only one-sided but his partisanship soon turns him into an intolerant and a fanatic. In general it is true that nothing which cannot stand up under discussion or criticism is worth defending”
~James E. Talmage, Improvement Era, Jan. 1920, p. 204

“If faith will not bear to be investigated; if its preachers and professors are afraid to have it examined, their foundation must be very weak.”
~George A. Smith, Journal of Discourses, Vol. 14, p. 216

“Man must learn to know the universe precisely as it is, or he cannot successfully find his place in it. A man should therefore use his reasoning faculty in all matters involving truth, and especially as concerning his religion. He must learn to distinguish between truth and error.”
~John A. Widtsoe, A Rational Theology, p. 8

“Now I have mentioned freedom to express your thoughts, but I caution you that your thoughts and expressions must meet competition in the market place of thought, and in that competition truth will emerge triumphant. Only error needs to fear freedom of expression. Seek truth in all fields, and in that search you will need at least three virtues; courage, zest, and modesty. The ancients put that thought in the form of a prayer. They said, 'From the cowardice that shrinks from new truth, from the laziness that is content with half truth, from the arrogance that thinks it has all truth—O God of truth deliver us’.”
~Hugh B. Brown, BYU Speech, March 29, 1958