Be humble about what you know.  Do not be over-confident about what you know.  It's not yours.  You learned it from someone else.  And any intellectual talents you may have, are gifts.  Any inherent wisdom you have is also a gift.  Instead of patting yourself on the back, be thankful.

Holy balls!  All the yes to this one!  The world, your world, gains nothing by withholding your knowledge, talents, and gifts OR pretending you are the end-all be-all on any subject matter.  Yes, you are lovely and good at what you may know or do.  I believe you are.  But you got what you have or know from somewhere or something.  Even the experts had teachers.  I will never diminish hard work, you earned it for sure, however, sharing your greatness with others suits you well when done in an effort to help them be better, not prove you are better than them.