From Lucretius’ De Rerum Natura:
“Athens, that famous name, first gave to sickly man
Fruit bearing crops long ago and with them
Created life anew and called for laws
And first offered the sweet comforts of life
When she produced a man with such a soul
That he once divulged everything from his truth-telling tongue.
Though his life has ended, thanks to his divine discoveries,
His glory has been carried abroad and now nears the heavens.
For he saw then that everything which is needed for life
Has already been set aside for mortal man and that
As far as they were able, their life was already safe…”
Primae frugiparos fetus mortalibus aegris
dididerunt quondam praeclaro nomine Athenae
et recreaverunt vitam legesque rogarunt
et primae dederunt solacia dulcia vitae,
cum genuere virum tali cum corde repertum,
omnia veridico qui quondam ex ore profudit;
cuius et extincti propter divina reperta
divolgata vetus iam ad caelum gloria fertur.
nam cum vidit hic ad victum quae flagitat usus
omnia iam ferme mortalibus esse parata
et, pro quam possent, vitam consistere tutam…
The man at Athens? Epicurus, of course.
Sallust, Bellum Catilinae 8
“The achievements of the Athenians were, as I see it, great and magnificent enough, but perhaps a little less so than is commonly believed. But, because the most talented writers happened to go there, the achievements of the Athenians are celebrated throughout the world as the greatest ever.”
Atheniensium res gestae, sicuti ego aestumo, satis amplae magnificaeque fuere, verum aliquanto minores tamen, quam fama feruntur. Sed quia provenere ibi scriptorum magna ingenia, per terrarum orbem Atheniensium facta pro maxumis celebrantur.
Velleius Paterculus has his own take on this:
“My wonder passes from clustering in certain times to cities. A solitary Attic city bloomed with more works of every kind of eloquence than the rest of Greece together, to the point that you might believe that the bodies of that race were separated into different cities, but that the geniuses were enclosed only within the walls of Athens. I find this no more surprising than the fact that no Argive, Theban or Spartan was considered worthy of note while he was alive or after he died. These cities, though preeminent for other things, were intellectually infertile, except for Pindar’s single voice which graced Thebes—for the Laconians mark Alcman as their own wrongly.”
 Transit admiratio ab conditione temporum et ad urbium. Una urbs Attica pluribus omnis eloquentiae quam universa Graecia operibus usque floruit adeo ut corpora gentis illius separata sint in alias civitates, ingenia vero solis Atheniensium muris clausa existimes. 2 Neque hoc ego magis miratus sim quam neminem Argivum Thebanum Lacedaemonium oratorem aut dum vixit auctoritate aut post mortem memoria dignum existimatum. 3 Quae urbes eximiae alias talium studiorum fuere steriles, nisi Thebas unum os Pindari inluminaret: nam Alcmana Lacones falso sibi vindicant.
Here Velleius moves from the clustering of intellects in time to their clustering in space. Although, to be fair, it seems that one would be impossible without the other…