As a surgeon for three decades, Ben Carson carefully balanced his responsibilities as a physician with his deeply religious personal philosophy.

And as a presidential candidate, he has offered views — on a variety of issues, including vaccines, climate change and creationism — that have endeared him to some conservative voters, but perplexed some of his science-minded former colleagues.

For example, during a recent Republican debate, he backed the view of the medical community that autism was not caused by vaccines, but he raised eyebrows by suggesting that they should be spread out.

In a recent interview with The New York Times, Dr. Carson elaborated on his views on a number of scientific, religious and medical topics:

On Vaccines

Some people feel that I make the declaration and everybody has to march to my drum.

My point was that there are a lot of people who are so concerned about the load of vaccines that they are getting in a very short period of time that they may abandon the use of vaccines altogether, which would be a very significant public health issue for us. I think we have to be willing to talk with them and to look at alterations in schedule.