I am not sure if there is an innate tendency to overlook or dismiss our shortcomings. If there were, I don’t think we, as a society, would have advanced to the level that we have. However, presupposing that there is an evolved predilection (since I don’t believe in Intelligent Design) towards ignoring our shortcomings; couldn’t that actually works towards our advantage?
Now at first this may seem odd to say that an instinctive desire to cast aside our shortcomings works towards our benefit, but you must also consider the flip side of being preoccupied with personal shortcomings. Many times fear and depression are the result of being focused too much on our shortcomings, which ultimately will have a stultifying effect on personal progress. Hence, there is a good evolutionary strength behind being sometimes oblivious to our shortcomings so that we can overcome the immediate task at hand.

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