A fundamental principle of psychophysics is that people's ability to discriminate change in a physical stimulus diminishes as the magnitude of the stimulus increases. We find that people also exhibit diminished sensitivity in valuing lifesaving interventions against a background of increasing numbers of lives at risk. We call this psychophysical numbing. Studies 1 and 2 found that an intervention saving a fixed number of lives was judged significantly more beneficial when fewer lives were at risk overall. Study 3 found that respondents wanted the minimum number of lives a medical treatment would have to save to merit a fixed amount of funding to be much greater for a disease with a larger number of potential victims than for a disease with a smaller number. The need to better understand the dynamics of psychophysical numbing and to determine its effects on decision making is discussed.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
“38,000 Shoes Stand For Loss In Lethal Year,” (1994) The Register-Guard, September 21, 6A.
Cooper, A. (1994). All Things Considered. Washington, DC: National Public Radio, July 25.
Fechner, G. T. (1860). Elemente der Psychophysik. Leipzig: Breitkopf und Härtel.
Galanter, E. (1962). “The Direct Measurement Of Utility And Subjective Probability,” American Journal of Psychology 75, 208–220.
Hersey, J. (1946). Hiroshima. New York: Bantam.
Humphrey, N. (1981). “Four Minutes To Midnight.” Quoted in R. J. Lifton and N. Humphrey (eds.), In A Dark Time. Cambridge, MA: Harvard University, 21–22.
Kahneman, D., and A. Tversky. (1979). “Prospect Theory: An Analysis of Decision Under Risk,” Econometrica 47, 263–291.
Lifton, R. J. (1967). Death In Life: Survivors Of Hiroshima. New York: Random House.
Purvis, A. (1994). “All the Hatred in the World,” Time, June 13, 36–37.
Rummel, R. J. (1995). “The Holocaust in Comparative and Historical Perspective.” Paper delivered at the conference on “The ‘Other’ as Threat—Demonization and Antisemitism.” Hebrew University of Jerusalem, June.
Schell, J. (1982). The fate of the earth. New York: Alfred A. Knopf.
Stevens, S. S. (1975). Psychophysics. New York: Wiley.
Summers, C., P. Slovic, D. Hine, and D. Zuliani. (in press). “’Psychophysical Numbing’: An Empirical Basis for Perceptions of Collective Violence.” In C. Summers and E. Markusen (eds.), Collective Violence: Harmful Behavior in Groups and Governments.
Tversky, A., and D. Kahneman. (1981). “The Framing of Decisions and the Psychology of Choice,” Science 211, 453–458.
Weber, E. H. (1834). “De Pulsu, Resorptione, Auditu et Tactu.” In Annotationes Anatomical et Physiological. Leipzig: Koehler.
World News Tonight. (1994a). “Many Rwandan Refugees Are Dying of Cholera.” New York and Washington, DC: American Broadcasting Corporation, July 22.
World News Tonight. (1994b). “U.S. Army Begins Water Purification in Rwanda.” New York and Washington, DC: American Broadcasting Corporation, July 26.
About this article
Cite this article
FETHERSTONHAUGH, D., SLOVIC, P., JOHNSON, S. et al. Insensitivity to the Value of Human Life: A Study of Psychophysical Numbing. Journal of Risk and Uncertainty 14, 283–300 (1997). https://doi.org/10.1023/A:1007744326393
- decision making
- life saving
- value of life
- risk-benefit analysis
- psychophysical numbing