I am really confused here. I cant imagine that 'superiority' can be countable in this given context. Can anyone explain this usage. I am intuitively inclined to drop an article in this example altogether. Will it be a mistake?
The ranking by wealth of which Spencer so approved is but one example of a wider tendency for people to try to out-do each other. And that competition, whether athletic, artistic or financial, does seem to be about genetic display. Unfakeable demonstrations of a superiority that has at least some underlying genetic component are almost unfailingly attractive to the opposite sex.
I would leave it in otherwise you are changing the meaning. At the moment, it means that the person has one good talent, one demonstrable advantage or superiority over others, for example being a good athlete, or a good artist, or a financial advantage. If you take out 'a': 'unfakeable demonstrations of superiority' means that ther person is generally superior.
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