Magnus, Bernd.  "Perfectibility and Attitude in Nietzsche's Ubermensch'."  Review of Metaphysics 36 (March 1983): 633-659.

Excerpt:

“THIS paper consists essentially of three parts. The first part

argues the case for construing Nietzsche’s remarks about Uber
menschlichkeit as endorsing some (reasonably) specific set of char
acter traits, of “virtues” if you like. To be an ?bermensch, on this
reading, is to possess or exhibit certain traits of character, traits
which in the typical case are associated with notions of self-over
coming, sublimation, creativity, and self-perfection. An ?ber
mensch, construed in this way, expresses Nietzsche’s vision of the
human ideal, of what human beings should or might be like. In
this sense Nietzsche merely continues the ancient project of artic
ulating the human ideal, the conception of human perfectibility.
Although Nietzsche’s answer may appear to be shockingly different,
the project of articulating a human ideal is scarcely radical. The
project qua project is no different than that of Plato or Aristotle,
the Stoics, Spinoza or Kant.”

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