Breakingone’sdietingruleorresolutiontoquitsmoking,procrastination,convenientlies,eventhefailureofentirenationstofollowthroughwithplanstocutgreenhousegasemissionsorkeepapandemicincheck-thesephenomenahavebeendiscussedbyphilosophersandbehaviouralscientistsasexamplesofweaknessofwillanddelaydiscounting.Despitethecommonsubjectmatterbothfieldshavetodaterarelyworkedtogetherformutualbenefit.Fortheempiricalliteratureishardlyaccessibletoareadernotfamiliarwitheconometrictheory;andresearchersinthebehaviouralsciencesmayfindphilosophicalaccountsinvokingdiscountingmodelsdifficulttounderstandwithoutinsideknowledgeofthedebatesandhistoricalbackground.NoraHeinzelmanntargetsthislacunabymakingtheideasandfindingsfrombothdisciplinesintelligibletooutsiders.Thisrevealsthatdiscounting-asphilosophershaveconceivedofit-isneithernecessarynorsufficientforweaknessofwill,eventhoughthereissubstantialoverlap.Heinzelmanndevelopsaricherdescriptiveaccountofweaknessofwillthatisbasedontheempiricallyfoundedassumptionthatweak-willedbehaviourisdeterminedbyuncertaintyaboutwhetherorwhenagoodmaterialises.Shealsoexplainswhyweaknessofthewillunderstoodinthiswayisirrational:theagentyieldstoacognitivebiasthatleadsthemtounderestimatethegreatergoodtheythinktheyoughttoandcanobtain.Finally,sheexplorespracticalimplicationsforindividualsandpolicymakers.
