This paper traces the semantic and constructional development of the complement-taking verb εὑρίσκω ‘find’ from Homeric Greek to Post-Classical Greek. First, the paper details the semantic development of εὑρίσκω using characteristics such as predicate type, semantic role of the subject and factivity. Subsequently, explanations are offered for the constructional development of εὑρίσκω, using insights from grammaticalization research such as reanalysis and analogy. In contrast to previous studies on Ancient Greek complementation which support the idea of a systematic Classical Greek opposition of factive participial versus non-factive infinitival complementation, this paper shows how bridging contexts of mental judgment εὑρίσκω with a participial complement do not follow this opposition as they are non-factive and changed their meaning (with reanalysis) before changing their complementation structure (through analogy). Also, by extending our view to the individual history of other cognitive predicates (ἐπίσταμαι, γιγνώσκω and οἶδα) the author shows that other cognitive predicates undergo similar developments from factive+object to factive+ACP to non-factive+ACI, although their individual histories are still in need of a systematic diachronic account. Thus, complementation patterns per period could be analysed in a more fine-grained way by analysing complementation patterns bottom-up from the semantic and constructional evolutions of individual predicates. Also, the findings from this paper provide evidence towards a diachronic solution of the so-called matching-problem: diachronically related semantic and constructional stages strongly motivate the choice of a specific complementation structure but absolute factivity oppositions in Classical Greek complementation are rather strong tendencies