In a 1974 commencement address, Richard Feynman described scientific integrity as a kind of utter honesty, a kind of leaning over backwards to tell the whole truth. We argue that investigators could tell more of the truth and increase the value of their papers by highlighting and discussing unexplained variation, a major source of which is individual differences. An argument that unexplained individual differences must have many sources is presented, and means of representing that variation are illustrated. We believe that such a change in reporting of research results is likely to advance the progress of scientific psychology, but perhaps the most compelling argument for what we propose is simply that telling the whole story as fully as possible is good scientific practice. The Appendix provides two examples of what we are urging, taken from recent psychological literature.
AllportG. W. (1937). Personality: A psychological interpretation. New York, NY: Holt, Rinehart & Winston.
2.
AllportG. W. (1961). Pattern and growth in personality. New York, NY: Holt, Rinehart & Winston.
3.
ArielyD. (2008). Predictably irrational: The hidden forces that shape our decisions. New York, NY: HarperCollins.
4.
BakerT. B.McFallR. M.ShohamV. (2008). Current status and future prospects of clinical psychology: Toward a scientifically principled approach to mental and behavioral health care. Psychological Science in the Public Interest, 9, 67–103.
5.
BemD. J. (2011). Feeling the future: Experimental evidence for anomalous retroactive influences on cognition and affect. Journal of Personality and Social Psychology, 100, 407–425.
6.
CampbellD. T. (1990). The Meehlian corroboration-verisimilitude theory of science. Psychological Inquiry, 1, 142–147.
7.
ChambersJ. M.ClevelandW.S.KleinerB.TukeyP. A. (1983). Graphical methods for data analysis. New York, NY: Chapman and Hall.
8.
ClevelandW. S.McGillM. (Eds.). (1988). Dynamic graphics for data analysis. New York, NY: Chapman and Hall.
9.
CronbachL. J. (1957). The two disciplines of scientific psychology. American Psychologist, 12, 671–684.
10.
DohertyM. E.AndersonR. B. (2009). Variation in scatter plot displays. Behavior Research Methods, 41, 55–60.
11.
FeynmanR. (1985). Surely you’re joking, Mr. Feynman!: Adventures of a curious character. New York, NY: W. W. Norton.
12.
FisherR. A. (1935). The design of experiments. Oxford, UK: Oliver & Boyd.
13.
GigerenzerG.HoffrageU. (1995). How to improve Bayesian reasoning without instruction: Frequency formats. Psychological Review, 102, 684–704.
14.
KlineR. B. (2004). Beyond significance testing: Reforming data analysis methods in behavioural research. Washington, DC: American Psychological Association.
15.
KluckhohnC.MurrayH. A. (1948). Personality in nature, society, and culture. New York, NY: Knopf.
16.
LamiellJ. T. (1981). Toward an idiothetic psychology of personality. American Psychologist, 36, 276–289.
17.
LincolnY. S.GubaE. G. (1985). Naturalistic inquiry. Thousand Oaks, CA: Sage.
18.
McGuireW. J. (1986). A perspectivist looks at contextualism and the future of behavioral science. In RosnowR.GeorgoudiM. (Eds.), Contextualism and understanding in behavioral science: Implications for research and theory (pp. 271–301). New York, NY: Praeger.
19.
McGuireW. J. (1989). A perspectivist approach to the strategic planning of programmatic scientific research. In GholsonB.ShadishW. R.NeimeyerR. A.HoutsA. C. (Eds.), Psychology of science (pp. 214–245). New York, NY: Cambridge University Press.
20.
MeehlP. E. (1978). Theoretical risks and tabular asterisks: Sir Karl, Sir Ronald, and the slow progress of soft psychology. Journal of Consulting and Clinical Psychology, 46, 806–834.
21.
MeehlP. E. (1990). Appraising and amending theories: The strategy of Lakatosian defense and two principles that warrant it. Psychological Inquiry, 1, 108–141.
22.
MillerG. A. (2004). Another quasi-30 years of slow progress. Applied & Preventive Psychology, 11, 61–64.
23.
PashlerH.McDanielM.RohrerD.BorkR. (2009). Learning styles: Concepts and evidence. Psychological Science in the Public Interest, 9, 105–119.
24.
ShampanierK.MazarN.ArielyD. (2007). Zero as a special price: The true value of free products. Marketing Science, 26, 742–757. doi: 10.1287/mksc.1060.0254
25.
SuppeF. (Ed.). (1977). The structure of scientific theories. Urbana: University of Illinois Press.
26.
WilkinsonL., & The Task Force on Statistical Inference. (1999). Statistical methods in psychology journals: Guidelines and explanations. American Psychologist, 54, 594–604.
