The Unabomber: An Extreme Reaction to Behavior Modification

Sep 5, 2023 | Historian

Historians’ Corner contributed by Dr. Andy Lattal

Kennon "Andy" Lattal

Dr. Andy Lattal is Centennial Professor of Psychology at West Virginia University, where, since 1972, he has taught and mentored 42 doctoral students. He has published research on a variety of topics related to the reinforcement and elimination of operant behavior and the history and philosophy of behavior analysis. A former Editor of the Journal of the Experimental Analysis of Behavior, he also has held major leadership positions in many of the major organizations dedicated to advancing behavior analysis. His service to behavior analysis has been recognized with SABA’s Distinguished Service to Behavior Analysis and its International Dissemination of Behavior Analysis awards. 

Andy Lattal
West Virginia University
Cambridge Center for Behavioral Studies, Member, Board of Directors

Between 1978 and 1995 in the United States there was a series of explosions involving bombs either planted or sent through the mails, averaging about once a year. The FBI labeled the, then unknown, individual responsible the “Unabomber” “because most of the bombings targeted universities or airlines” (Chase, 2000). One of those bombings involved a well-known psychologist closely identified with behavior modification, James V. McConnell, shown in Figure 1. Stern (2007) noted that “[a]lthough McConnell, writing to a colleague in 1989, stated that he ‘never was a ‘Skinnerian,’ and never will be’ he did, in fact, embrace Skinner’s main principles of shaping and modifying behavior from the get-go. He did …discard some aspects of Skinner’s strict approach and graft on what he believed to be needed additions.”

Figure 1. James V. McConnell posed circa 1960s, with the logo of his Worm Runner’s Digest.

Figure 1. James V. McConnell posed circa 1960s, with the logo of his Worm Runner’s Digest.

In 1959, McConnell launched The Worm Runner’s Digest (see Figure 2), a psychology journal that combined scientifically serious research on, mostly, classical conditioning of the planarian, a non-parasitic flatworm with remarkable regenerative abilities, and articles of a more humorous nature, often poking fun at his own research area. During the years of the Digest McConnell published several articles not only claiming to have shown classical conditioning in planaria, but also gains in acquisition of a conditioned response when a naïve planarian was fed another planarian that had been previously conditioned. McConnell’s various claims proved to be controversial, resulting in a series of back and forth experiments attempting to sort out fact from fiction about planarian conditioning.  

Figure 2. Cover of an early (1960) issue of The Worm Runner’s Digest. The first several issues were mimeographed, like this one.

Figure 2. Cover of an early (1960) issue of The Worm Runner’s Digest. The first several issues were mimeographed, like this one.

While McConnell was researching flatworm conditioning, an undergraduate student at Harvard University, Theodore Kaczynski, volunteered for a long-term study conducted there that was designed to test psychological stamina under difficult interrogation conditions. The interrogations later were described as “vehement, sweeping, and personally abusive” (Chase, 2000) and unethical (What Happened to Ted Kaczynski at Harvard? | HISTORY). The lead researcher was Henry Miller, a professor of psychology at Harvard and the creator of a famous projective test, the Thematic Apperception Test, or T. A. T. (see Robinson, 1992). The sponsor of the research was the United States Central Intelligence Agency (CIA). Things went badly for Kaczynski and the interviews were a contributing factor to the events described herein. 

Fast forward to the mid-1960s at the University of Michigan. McConnell was a popular professor, routinely offering wisdom and wit to large sections of psychology courses. He was quite visible on campus because of his teaching skills, charisma, and humor (as evidenced in no small part by his Digest). One of the topics of considerable interest in psychology in the 1960s was what then was called behavior modification, something McConnell wrote extensively about in both the professional and popular media, and talked about in his classes. Kaczynski was now also at Michigan working on his Ph.D. in mathematics. McConnell’s public persona and accompanying ideas likely brought him, and his teaching of behavior modification, to the attention of Kaczynski. After finishing his Ph.D., Kaczynski taught for a couple of years at UC Berkeley before resigning and moving to Montana to live a hermit’s life. 

Figure 3. Artist’s sketch of the Unabomber based on an eyewitness sighting of him following one of the bombing incidents.

Figure 3. Artist’s sketch of the Unabomber based on an eyewitness sighting of him following one of the bombing incidents.

Figure 4. Theodore Kaczynski at the time of his arrest on April 3, 1996.

Figure 4. Theodore Kaczynski at the time of his arrest on April 3, 1996.

Beginning in 1978 and ending in 1995, mail and planted bombs appeared around the country, capturing citizen concern and media attention. The perpetrator turned out to Kaczynski. On  November 15, 1985, a package arrived at McConnell’s home, where it was opened by one of his students. When it exploded, it blew a 6-inch hole in the table where it sat, sent the student to the hospital with arm and stomach wounds, and resulted in temporary deafness of both the student and McConnell, who was also in the room at the time of the explosion. Kaczynski’s targeting of McConnell seemed to be a perfect storm of Kaczynski’s general suspicion of technology and industrialism, his bad personal experience in the Harvard study, which has been incorrectly characterized as involving behavior modification, and McConnell’s very visible and often controversial views on technology and human behavior change.

The Unabomber’s 35,000-word manifesto, Industrial Society and Its Future, was controversially published on September 19, 1995, while Kaczynski was still at large. He threatened even more violence if it was not published. The New York Times and Washington Post agreed to publish it in hopes that he might be identified from clues contained therein. The points made in the manifesto continue to be debated as to their merits. Kaczynski’s writing style was recognized by his brother, who turned him in. Kaczynski pleaded guilty to murder in 1998 and was sentenced to prison for life. He died in a correctional facility in North Carolina on June 10, 2023 at age 81, by his own hand. He had late-stage cancer. 

Kaczynski’s distortion of the connection between his experience as a Harvard subject and even 1960s behavior modification is perhaps the most extreme and terrible outcome of a misrepresentation and misunderstanding of a science imaginable. On a totally different scale, Morris and his colleagues (e.g., Morris & Todd, 1992) have documented many distortions of and misrepresentations of modern behavior analysis. Science and its applications are public. As such they are always open to scrutiny resulting in comment, praise, and criticism. Accepting constructive feedback is central to any scientific endeavor, lest the discipline, like Kaczynski, lose touch with reality. Feedback always should be welcome and never shunned because it is something we don’t want to hear. It provides perspective and reminds behavior analysts of broader issues in the culture to which we need to attend in developing interventions. False “facts” and assessments, like Kaczynski’s, are an unfortunate part of contemporary life in America. Counterpoints to such falsification seem too often to fall on deaf ears, as likely would have a rational accounting to Kaczynski of the differences between McConnell’s assertions and Kaczynski’s unfortunate experience in “experiments” widely regarded as unethical. Nonetheless, behavior analysis’s only recourse is to listen, separate fact from fiction, respond appropriately, and devise interventions that reflect both the findings of the science and legitimate feedback from credible sources in larger communities outside our behavior-analytic circle. Hopefully, however strong the criticisms and reservations, an objection to what we are doing like that experienced by McConnell and his student in 1985 will never happen again.  


Chase, A. (2000). Harvard and the making of the Unabomber. The Atlantic.

Morris, E. K., Todd,  J. E. (1992). Case histories in the great power of steady misrepresentation. American Psychologist, 47 (11), 1441-1453.

Rilling, M. (1996). The mystery of the vanished citations: James McConnell’s forgotten 1960s quest for planarian learning, a biochemical engram, and celebrity. American Psychologist, 51(6), 589–598.

Robinson, F. G. (1992). Love’s story told: A life of Henry Murray. Harvard University Press.

Stern, L. (2008, August). James V. McConnell and behavior modification: Hyperbole and practice. Paper presented at the annual meeting of the American Psychological   Association, Boston, MA.


1 The impetus for this article was an inquiry to the author about The Worm Runner’s Digest from Rob Holdsambeck, the Executive Director of the Cambridge Center for Behavioral Studies. Thank you, Rob!