"(You) can't be the president unless you have a firm set of principles to guide you as you sort through all the problems the world faces," Bush said during a news conference, responding to a question about what he thought was important in running for president.

"And if I were asking questions to people running for office, I'd say, what are the principles that you will stand on, in good times and bad times," Bush said. "I would be very hesitant to support somebody who relied upon opinion polls and focus groups."

Besides knowing the "underpinnings" of a decision, Bush said people should ask presidential candidates about how they will get and take advice.

Whoever becomes president "is going to find this is a complex world with a lot of issues," Bush said. "And so my (second) question would be, how do you intend to set up your Oval Office so that people will come in and give you their advice."