It happened in 1955 when world-famous chemist Henry Eyring met with Elder Joseph Fielding Smith, who later became the 10th president of the LDS Church. They talked for about an hour and gentlemanly agreed to disagree, according to the biography "Mormon Scientist: The Life and Faith of Henry Eyring."
"Brother Smith, I have read your books and know your point of view, and I understand that is how it looks to you. It just looks a little different to me," Eyring said.
The reply implied the conversation was a little more animated.