This article aims to examine Constantine Lascaris’s work on Aristoteles’ ethical corpus. We consider evidence from the textual witnesses of the Nicomachean Ethics, the Eudemian Ethics, the Magna Moralia, and some other minor ethical writings, which belonged to Lascaris, in order to reconstruct his working methods. We also explore Lascaris’ own statements about virtuous life; a life devoted to the service of the common good, to philosophy and to the study of texts. For him philosophy was a way of life, rather than simply a discourse. We look at the link between written culture and philosophical life and propose further research into how Byzantine and Renaissance scholars understood their own intellectual activities to be a special kind of spiritual exercise intended to promote moral improvement in both individuals and societies.