Paul I appreciate your comment that the "
inferiority feeling is not a personal disaster but can propel us along". That is a key piece that I had not considered mentioning. Yes indeed, none of us, not even the most accomplished human, has achieved all he has to give and achieve. Perhaps this is not as much an inferiority feeling as a true sense of humility and a recognition that we are so very complex and have such great potential for good that we are never "done". It is not arrogant to wish to achieve the best self for mankind. The trick is not to slip into the arrogance of being "better than others" or the converse vainity of feeling to have achieved notariety as the "chief of sinners". Both notions are exceedingly vain and unbecoming.
When you look at Adler's notion of vanity, there is a deep ditch on both sides of the road of being a fellow man. Wise men and encouraged men just must strive to achieve the best available self to add to the "stream of human evolution" "sub specie aeternitatis". What a nice self check Adler gives us and if we focus on this, we will in the notion of Mueller, "Be a Blessing".