"Oh, those Greeks! They knew how to live: what is needed for that is to stop bravely at the surface, the fold, the skin; to worship appearance, to believe in shapes, tones, words - in the whole Olympus of appearance! Those Greeks were superficial - out of profundity!" [a]
If I had to choose the one passage by Nietzsche that has most significantly shaped my own thinking as a philosopher, both on and off the catwalk, it would be this one.
And, interestingly, despite his onto-theological penchant for indulging in what Nietzsche would characterise as beautiful soul twaddle [b], D. H. Lawrence also seems inspired by this idea of Greek (and Sicilian) superficiality in his 'Introduction to Mastro-don Gesualdo, by Giovanni Verga' [c] ...
Regrettably - and unlike Lawrence - I've never lived in Sicily [d], nor even visited this "sun-beaten island whose every outline is like pure memory" . But I'm happy to accept the literary consensus and regard it as a magical location, which provides a clue not only to understanding modern Italy, but also the ancient Mediterranean world.
For according to Lawrence, not only are the Sicilians marked by an ironic fatalism, like the ancient Greeks, but they also lack psychic depth. In other words:
"The Sicilian has no soul, except that funny little naked man who hops on hot bricks, in purgatory, and howls to be prayed into paradise [...] He can't be introspective, because his consciousness, so to speak, doesn't have any inside to it." .
Developing his theme, Lawrence continues:
"The Sicilians today are supposed to be the nearest descendants of the classic Greeks, and the nearest thing to the classic Greeks in life and nature. And perhaps it is true. Like the classic Greeks, the Sicilians have no insides, introspectively speaking." 
Unfortunately, however, unlike the classic Greeks, the Sicialians have no external gods. This, for Lawrence at least, is a problem and represents a great loss.
Why? Because, says Lawrence, people who live in the sun like flowers - i.e., beautiful but soulless - still need "the bright and busy gods outside" in order to make them feel heroic in the old Homeric sense with "the same easy conscience, the same queer openness [...] and the same ancient astuteness" .
Whilst the more soulful - more Christian - races of Northern Europe "have got over the old Homeric idea of the hero, by making the hero self-conscious, and a hero by virtue of suffering and awareness of suffering" , the Sicilians only feel this sort of thing in short spasms and it is unnatural to them.
In fact, Lawrence concludes, it's pointless to suggest that a Sicilian learn how to develop northern (or Russian) inwardness: "You might as well say the tall and reckless asphodel of Magna Graecia should learn to be a snowdrop." 
Of course, even if the modern Sicilians have lost the bright and busy gods, still they possess the undying beauty of the island itself:
"And we must remember that eight-tenths of the population of Sicily is maritime or agricultural [...] and therefore practically the whole day-life of the people passes in the open, in the splendour of the sun and the landscape, and the delicious, elemental aloneness of the old world. This is a great unconscious compensation. But what a compensation, after all! [...] and you can't read Mastro-don Gesauldo without feeling the marvellous glow and the glamour of Sicily, and the people throbbing inside the glow and the glamour like motes in a sunbeam. [...]
And perhaps it is because the outside world is so lovely, that men in the Greek regions have never become introspective. They have not been driven to that form of compensation. With them, life pulses outwards, and the positive reality is outside. There is no turning inwards. So man becomes purely objective. And this is what makes the Greeks so difficult to understand: even Socrates." 
These, then, are the three key words of Greek profundity: superficiality, externality, and objectivity. And these the three key words of the ancient Greek character: singleness, carelessness, dauntlessness [e].
If you want to become an artist or practice la gaya scienza - if you want to become heroic in the old sense - then you must abandon ideas of salvation or retreating inside yourself in order to twist the soul into knots; instead, concentrate on care of the self as an aesthetic and ethical project that aims for splendour (becoming what Lawrence elsewhere terms an aristocrat of the sun) [f].
[a] Nietzsche, The Gay Science, ed. Bernard Williams, trans. Josefine Nauckhoff, (Cambridge University Press, 2001), Preface to the second edition (4), pp. 8-9.
[b] This amusing phrase can be found in note 951 (Spring-Fall 1887) of The Will to Power, trans. Walter Kaufman and R. J. Hollingdale, ed. Walter Kaufman, (Vintage Books, 1968), p. 499.
[c] D. H. Lawrence, 'Introduction to Mastro-don Gesualdo, by Giovanni Verga', in Introductions and Reviews, ed. N. H. Reeve and John Worthen, (Cambridge University Press, 2005), pp. 145-156. Future page references to this work will be given directly in the text. Readers are encouraged to also read the two earlier versions of Lawrence's Introduction which appear as Appendices II and III (pp. 369-378 and 379-389). This passage from Version I is particularly Nietzschean-sounding in its vision of the Greeks:
"The Greeks were far more bent on making an audacious, splendid impression than on fulfilling some noble purpose. They loved the splendid look of a thing, the splendid ring of words. Even tragedy was to them a grand gesture, rather than something to mope over. Peak and pine they would not, and unless some Fury pursued them to punish them for their sins, they cared not a straw for sins: their own or anyone else's.
As for being burdened with souls, they were not such fools." [376-77]
[d] Lawrence and his wife Frieda spent two years living in Sicily in the early 1920s, at the Fontana Vecchia, on a hill above Taormina. Like many others before him, including - perhaps most famously - Goethe, Lawrence was captivated not just by the island, but also its people, flora, and fauna and he wrote some of his loveliest poetry on the island. In Version I of his Introduction to Mastro-Don Gesualdo, he confesses:
"Perhaps the deepest nostalgia I have ever felt has been Sicily [...] Not for England or anywhere else - for Sicily, the beautiful, that which goes deepest into the blood. It is so clear, so beautiful, so like the physical beauty of the Greek." .
[e] D. H. Lawrence, 'Introduction [Version I] to Mastro-Don Gesualdo, by Giovanni Verga', Introductions and Reviews, Appendix II, p. 378.
[f] See the poem 'Aristocracy of the sun', in D. H. Lawrence, The Poems, Vol. I, ed. Christopher Pollnitz, (Cambridge University Press, 2013), p. 457. See also the related verses 'Sun-men' and 'Sun-women', p. 456.