One of the most important things, in my opinion, is being able to admit that you don't know or don't understand something. The opposite attitude gets in the way of learning new things, which is really bad for programmers.
To give "urge" more meaning: These days I get a noticeable weird feeling in my gut if I'm working in a environment where there are too many unknowns.
That's fear for me. Always a chance I'll knock something important over...
further, try to create an environment where others (particularly others who are less powerful) feel comfortable voicing their concerns and are secure enough to state when they don't know or don't understand something.
e.g. if people are worried they are going to be fired or ridiculed in a group setting for not knowing a thing then it would be unreasonable to expect them to say "i don't know".