Mark Twain was making fun - the essay isn't supposed to be taken seriously. His conclusion would also be wrong, since the grammatical gender has nothing to do

Mark Twain was making fun - the essay isn't supposed to be taken seriously. His conclusion would also be wrong, since the grammatical gender has nothing to do with he biological gender - it's the gender assigned to all diminutive forms, regardless of grammatical gender. E.g. "der Vater" (the father) becomes "das Väterchen" just as well without loosing his proverbial balls in the process.