Replication in Psychology: A Historical Perspective

Replication in Psychology: A Historical Perspective

The reproducibility of psychological findings has generated much discussion of late. However, the question of replication is not a new one for psychologists.

Psychologist have long debated how best to measure their phenomena, how to design their studies, how best to interpret their data, and whether their findings have a broader relevance.

This interactive timeline offers the reader a brief guide to this longer history. I define replication fairly broadly, but attempt to not simply offer a history of psychology in its entirety. Instead, I have focused on famous replication controversies from the past alongside the development of psychology’s favored research methods.

I am personally quite agnostic as to the value of the current interest in direct replication. My worry is that it distracts (as is often the case in psychology) from questions of external validity. My goal is to provide a richer context for contemporary controversies animating psychology.

I welcome corrections, updates, and suggestions of relevant topics. Please contact me at mpettit at

Michael Pettit

I am an associate professor of Psychology and Science & Technology Studies at York University. My historical research focuses on psychology as a public science and the discipline’s relationship with others fields as such medicine, sexology, and the other human sciences.