openness or skepticism

Here are a few Carl Sagan quotes taken from his book The Demon-Haunted World which I am currently reading (my emphasis in bold):

"...the heart of science is an essential balance between two seemingly contradictory attitudes -- an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. The collective enterprise of creative thinking and skeptical thinking, working together, keeps the field on track."

"If you're only skeptical, then no new ideas make it through to you. You never learn anything. You become a crotchety misanthrope convinced that nonsense is ruling the world. (There is, of course, much data to support you.) Since major discoveries at the borderlines of science are rare, experience will tend to confirm your grumpiness. But every now and then a new idea turns out to be on the mark, valid and wonderful. If you're too resolutely and uncompromisingly skeptical, you're going to miss (or resent) the transforming discoveries in science, and either way you will be obstructing understanding and progress. Mere skepticism is not enough."

"...science requires the most vigorous and uncompromising skepticism, because the vast majority of ideas are simply wrong, and the only way to winnow the wheat from the chaff is by critical experiment and analysis. If you're open to the point of gullibility and have not a microgram of skeptical sense in you, then you cannot distinguish the promising ideas from the worthless ones. Uncritically accepting every proffered notion, idea, and hypothesis is tantamount to knowing nothing. Ideas contradict one another; only through skeptical scrutiny can we decide among them. Some ideas really are better than others."

"No one can be entirely open or completely skeptical. We all must draw the line somewhere. An ancient Chinese proverb advises, 'Better to be too credulous than too skeptical,' but this is from an extremely conservative society in which stability was much more prized than freedom and where the rulers had a powerful vested interest in not being challenged. Most scientists, I believe, would say, 'Better to be too skeptical than too credulous.' But neither is easy. Responsible, thoroughgoing, rigorous skepticism requires a hard-nosed habit of thought that takes practice and training to master. Credulity -- I think a better word here is 'openness' or 'wonder' -- does not come easily either. If we really are to be open to counterintuitive ideas in physics or social organization or anything else, we must grasp those ideas. It means nothing to be open to a proposition we don't understand."