Does being prideful carry mostly disadvantages for the self or are there some important outweighing benefits?

Too much pride is one of the deadliest sins. Just be yourself. Anything else will weigh you down. Have a sense of ones self. Just don't carry it too far. The outweighing benefits are that you maintain your strength and integrity. Too much pride? Leads to Arrogance. Too little, you may lose yourself. Find a balance.

It depends. Hubris is a sure way to disaster, for ones self, and others. But having sufficient critical self-respect to pursue ones convictions, remaining ready to change them when critical thought and experience undermines them - and taking some pride in that human attribute - seems to me to always have outweighing benefits, whatever the costs. To be human is to be sometimes foolish. To recognize that, and proceed accordingly, is wise. I reckon most convictions are mostly measures of our present ignorance. And so, most of all, is hubris.

quote from http://courseinmiracles.com/

Who is the light of the world except God’s Son? This, then, is merely a statement of the truth about yourself. It is the opposite of a statement of pride, of arrogance, or of self-deception. It does not describe the self-concept you have made. It does not refer to any of the characteristics with which you have endowed your idols. It refers to you as you were created by God. It simply states the trusignifiesrdivisionllusion it signifys devision as in "i have something over another"

Pride and egotism, which you seem to be referring to, are not the same.

"Pride is the recognition of the fact that you are your own highest value... that your character, your actions, your desires, your emotions are the products of the premises held by your mind—that as man is a being of self-made wealth, so he is a being of self-made soul—that to live requires a sense of self-value...that the first precondition of self-esteem is that radiant selfishness of soul which desires the best in all things, in values of matter and spirit, a soul that seeks above all else to achieve its own moral perfection, valuing nothing higher than itself...which one achieves by never accepting any code of irrational virtues impossible to practice and by never failing to practice the virtues one knows to be rational—by never accepting an unearned guilt and never earning any, or, if one has earned it, never leaving it uncorrected—by never resigning oneself passively to any flaws in one’s character—by never placing any concern, wish, fear or mood of the moment above the reality of one’s own self-esteem." condensed from http://aynrandlexicon.com/lexicon/pride.html

If "pride" is given this respect by your conscious ambition to be the best that you can be in all things, it does not need to be a negative. Indeed, it must be a positive, or you will wonder why you feel that everything you achieve makes you feel as if you want to hide under a rock---so that no one sees the smile of your soul lest they misinterpret it for egotism.

ADDED:

Sometimes "pride" is associated with "narcissism." That is not "pride" either, in the sense of the above discussion.

Pride as a counter balance to shame is a burden, pride as ongoing peaceful contented activity is healthy ego, gladness for being. The unhealthy ego is sure to attack you for it.

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