When the hardest person to convince is yourself

In a time when I question my adamance in many decisions, i find this quote most appropriate:

Most men, including those at ease with the problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues and which they have woven into the fabric of their lives.

~Tolstoy~

Does it take a truly great person to realise that egos should not impede our good judgement?
Still I doubt it would make any difference at all.