(Picture from the cover of Gumshoe, Little, Brown and Co., 1988)
Josiah "Tink" Thompson is best known for his enormously influential
1967 book Six Seconds in Dallas, which represented the first attempt to
analyze the assassination reasonably scientifically. I say
"reasonably" only because Thompson was trained in philosophy, not
science, and for him to have produced the quality of book that he did
represented an enormous achievement. The fact that certain of his scientific
approaches and deductions fell a little short does not take away from his
achievement, especially for the first such work.
Thompson graduated from Yale in 1957, and then spent two years as a naval frogman. He studied the philosopher Sören Kierkegaard for a year in Denmark, and in 1964 received a Ph.D. from Yale, with Kierkegaard as his professional specialty. He then took a position as Assistant Professor of Philosophy at Haverford College, outside Philadelphia, where he eventually became a full professor.
President Kennedy was assassinated while Thompson was working on his Ph.D. at Yale. He became interested in the assassination the moment it happened, figuring along with so many others that Jack Ruby's killing Oswald had to be more than just coincidence. He followed developments in the case, and even researched the 26 volumes a little on his own while at Yale, but put it aside in favor of protesting against the Vietnam War. While at Haverford, he was arrested with some other faculty members during one protest, and his lawyer turned out to be none other than Vincent Salandria, of Philadelphia. The resulting discussions rekindled Thompson's interest in the assassination, and he was soon hooked. He became a consultant to Life magazine and shortly afterward published Six Seconds.
The detective-like experience of working on the Kennedy assassination appealed enough to Thompson that he quit Haverford in 1976 and went to northern California to become a private investigator. In 1979 he became an independent investigator, and later was named Best Detective of 1987 by the Bay Guardian. In 1988 he wrote the famous Gumshoe, on his life as a private-eye. Through it all, he has remained involved with the JFK assassination, if not terribly active. Most recently, he delivered a searing blast at Prof. James Fetzer and others involved with Fetzer's book Assassination Science, at JFK Lancer's annual conference, Dallas, 20 November 1998, in a classic address entitled "Why the Zapruder Film is Authentic" .
Thompson also wrote a brief letter to The New York Review of Books in reply to Richard Popkin's 1966 article "The Second Oswald: The Case for a Conspiracy Theory." This letter seems to have been long since forgotten.
Additional biographical information on Josiah Thompson is contained in Calvin Trillin's "The Buffs" and in Clint Bradford's introduction to Thompson's address (from Bradford's web site). The latter focuses more on Thompson's private-eye work, the former more on his early history.