Scholiast on Plato, Laches, p. 187 b.
The proverb, “in the pithos is the potter’s art,” about those who skip the first lessons and take hold of the greatest tasks which are properly the last.
Παροιμία, ἐν πίθῳ τὴν κεραμείαν, ἐπὶ τῶν τὰς πρώτας μαθήσεις ὑπερβαινόντων, ἁπτομένων δὲ τῶν μειζόνων καὶ ἤδη τῶν τελειοτέρων.
Corpus Paroemiographorum Graecorum, Zenobius, III, 65.
“I learn the potter’s craft on the pithos”; a proverb upon those who skip the first lessons, and immediately attempt greater things; as if anyone who was learning to be a potter, before learning to mould plates or any other small thing, should undertake a pithos.
Ἐν πίθῳ τὴν κεραμείαν μανθάνω: Παροιμία ἐπὶ τῶν τὰς πρώτας μαθήσεις ὑπερβαινόντων, ἁπτομένων δὲ εὐθέως τῶν μειζόνων. Ὡς εἴ τις μανθάνων κεραμεύειν, πρὶν μαθεῖν πίνακας ἢ ἄλλο τι τῶν μικρῶν πλάττειν, πίθῳ ἐγχεροίη.
The fact that there was a Greek proverb on the folly of attempting large vases before a thorough knowledge of the craft has been acquired, shows how common was the realization of the difficulty of the task.
Plutarch, Quaestiones conviviales, II, p. 636 c.
Polykleitos the modeler said that the work is most difficult when the clay stands the test of the nail (?).