Timmerman is a contemporary philosopher working in normative ethics and the philosophy of action, with particular focus on the temporal dimensions of moral obligation. Their work examines how and when obligations come into force relative to the actions they require, contributing to debates in deontic logic and practical reasoning.
Argued for time-indexed accounts of moral obligation, distinguishing when an obligation holds from when the obligated action occurs
Contributed to debates on prospective versus synchronic moral requirements
Applied action-theoretic analysis to problems in normative ethics