Monitoring our errors enables humans to adapt behavior whenactions fail to result in desired outcomes. Post-error adaptationshave been studied extensively using simple laboratory taskswhere people typically slow down after errors. Few studies,however, examined such behavioral adaptations in morecomplex tasks such as reasoning. In two experiments weinvestigated how participants adapt their behavior based onevaluative feedback in syllogistic reasoning tasks.Experiment 1 demonstrates that participants’ likelihood to givea logically correct response increased throughout theexperiment when given feedback. This feedback effect waslimited to syllogisms that have no logical conclusion and thusmostly driven by an increase in participants’ “No validconclusion” responses. Experiment 2 investigates post-erroradaptations on a trial-level and shows that participants with ahigh accuracy slowed down after errors while participants witha low accuracy slowed down after correct responses.Implications on error-monitoring and reasoning research arediscussed.