The sentence of the OP suggests that women's level of 'feminine incompetence' is not simply stated/determined, as we could if you asked, "Can the person count to three." To such a question one can say, "Yes they have that competence." But in the case at issue, women's abilities to deal with and overcome social obstacles, there are all kinds of levels; further this issue is not intrinsic to the woman, but relates to her circumstances.
She is not really talking in our sense of 'competence', but rather whether women will be able to suceed in the face of social complexities and difficulties.
The passage ends with
Here and there is born a Saint Theresa, foundress of nothing, whose loving heart-beats and sobs after an unattained goodness tremble off and are dispersed among hindrances, instead of centring in some long-recognizable deed.
"dispersed among hindrances" is related to this 'incompetence' which is, in other words insufficient, luck, resources, and opportunities. Saint Theresa (Teresa) is one of those rare successes.
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In my opinion, Joan's line suggests somewhat of a misunderstanding. (That's my impression at least.) The writer is NOT saying women lack a basic competence comparable to the ability to count three.
Joan in part (post #2): If women were all equally incompetent (unable to count to three),
D. Everyone who lives near that factory seems really unhappy. It must you must have done it. people who are under 30 years old. give off a dangerous chemical.
"A false-causality fallacy is based on the mistaken assumption that because one event follows another, the first event caused the second."
