Parataxis often occurs when a thought naturally subordinate is made independent for the sake of emphasis or liveliness. Such rhetorical parataxis occurs chiefly in the orators and in Pindar. So especially when μέν and δέ are used to coördinate two contrasted clauses, the former of which is logically subordinate and inserted to heighten the force of the latter. Here English uses whereas, while. Thus,
αἰσχρόν ἐστι, εἰ ἐγὼ μὲν τὰ ἔργα τῶν ὑπὲρ ὑ_μῶν πόνων ὑπέμεινα, ὑ_μεῖς δὲ μηδὲ τοὺς λόγους αὐτῶν ἀνέξεσθε
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].