Abstract
The aim of the article is to draw attention to concessive clauses introduced by οὐδ'εἰ, οὐδ' ἐάν, ο ὐδ' ἄν, etc. as hardly any attention has been paid to these so far. When dealing with these clauses, some standard Ancient Greek grammar books mention negative (conditional-) concessive conjunctions (Basile 2001, p. 770) and negative concessive clauses (Smyth 1984, p. 539).
However, as my article shows, these subordinate clauses are not really negative because the negative part in οὐδέ has under its scope the main clause, as in the following example: οὐδὲ γὰρ εἰ πάνυ προυθυμεῖτο ῥᾴδιον ἦν ~ for even if he had been very eager to do so, it would not have been easy (Xen. Anab. 3.4.15.3).
The main clause does not need to have, but it can have, its own negator or n-word, while the subordinate clause undergoes some kind of negative neutralisation, as preponed οὐδ' εἰ clauses prove. Similar phenomenon can be observed in postponed οὐδ' εἰ clauses with negative apodosis.