Dear all,
We are delighted to invite you to today's London Judgment and Decision-Making (LJDM) seminar!
When: Wednesday, May 13, 2026, 17:15–18:15 UK time
Where: In person in room 675 (IOE) & Zoom
Speakers: Dr Ansgar D. Endress (Department of Psychology, City St George’s, University of London) & Prof Peter Ayton (Centre for Decision Research, University of Leeds)
Title: Bounded Morality: The Psychophysics of Morality (and decision making).
Abstract: Variance in moral decisions is often attributed to variance in the relative dominance of two distinct approaches: utilitarianism (maximizing good) and deontology (following rules). We propose a unitary psychophysical model where moral decisions operate like other perceptual systems, and track the subjective (information-theoretic) certainty that outcomes achieve the greater good – given representational noise in a magnitude-estimation system governed by Weber’s law, and where utilitarian and deontological responses are the high- vs. low- uncertainty limit cases. Our experimental participants rated the acceptability of sacrificing fewer ‘victims’ to save more ‘beneficiaries.’ Consistent with this model, acceptability tracked the Weber ratio of beneficiaries to victims, but not utility or harm. When uncertainty was decreased (using decisions concerning economic goods that had clearer values than decisions concerning human lives) responses became more ‘utilitarian’; when the attention to victims was increased via emotional manipulations, responses became more ‘deontological’, but always tracked the Weber ratio of beneficiaries to victims. Several large language models reproduced some aspects of our data, yet behaved qualitatively differently from humans and were much more sensitive to both harm and utility than to Weber ratios. We also show that the same model provides a mechanistic explanation of loss-aversion in decision making. People, but not machines, thus seek the greater good, but do so under perceptual noise.
Best,
Hadeel, Joel, and Calvin
London Judgment and Decision-making Group