Abstract
BACKGROUND: Beliefs about free will are central to philosophical and scientific conceptions of agency, and experimental work suggests that weakening such beliefs can reduce honesty, self-control, and helping. Yet little is known about how disbelief in free will influences moral reasoning in classic dilemmas contrasting utilitarian and non-utilitarian responses. METHODS: Three randomized studies were conducted with Venezuelan university students (N = 88 per study). Participants read either an adapted deterministic passage adapted from Crick or a neutral neuroscience text, then responded yes/no to the Spur, Footbridge, or Singer "Drowning Child" dilemmas. Fisher's exact tests, with follow-up logistic regressions, assessed effects of condition on moral choices. RESULTS: Responses showed the expected baseline patterns across dilemmas. The determinism manipulation reduced willingness to intervene in the Spur dilemma (p = 0.0385, fewer participants pulled the switch) and reduced willingness to help in the Singer scenario (p = 0.0261), but had no detectable effect on Footbridge judgments (p = 0.783). CONCLUSION: Inducing disbelief in free will appears to reduce proactive moral intervention rather than increasing willingness to endorse direct personal harm.