This is not what is meant by total depravity. First off, what the author originally describes and says is the "very definition" of total depravity is actually just original sin. Total depravity merely says that the sinful nature of man infects every aspect of his being. It does not say that man is as depraved as he can possibly be, certainly man is capable of and often does much good. It merely says that the sinful nature of man extends to his entire ("total") being.
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