The case marking of reciprocal and reflexive pronouns in an argumental function

A remarkable property of reciprocal and reflexive pronouns in Ancient Greek seems to have passed hitherto unnoticed: Both types of pronouns tend to receive a secondary (or "less common" or "deviant") morphological mark under certain conditions. The most statistically frequent "secondary" grammatical marking of such pronouns is the use of a preposition with accusative instead of the simple dative, but other alternations of cases and/or prepositions are possible as well. Although the secondary mark often turns to be the regular mark in later times, such tendency appears to be much greater than the media deviation from the "main" construction from our first documents in prose. To deal with such and similar phenomena, we propose to distinguish between "differential object marking" (following, i.a., Bossong and Aissen) and plain "different marking", and comment on the relations between both. We explore the possibility that the frequency of the "different" mark in reciprocals and reflexives be related with the decrease of transitivity inherent to the use of reciprocal and reflexive as verbal objects, and the mental imaginery involved in the case marking of some constructions.