Ted Kaczynski, the “Unabomber” currently serving a prison sentence for domestic terrorism, has a “very rational” critique of modern society, according to a University of Michigan professor who corresponds with Kaczynski.

“The reason why he sent the bombs was not so much because he thought killing people would do any good, the reason was that it gave him the leverage to force the publication of [his] manifesto,” David Skrbina, a lecturer at U of M-Dearborn, told The Chronicle of Higher Education. “In a sense he had this larger cause, which is a noble cause. If it turns out to be true that there is this vital threat to the planet or to humanity, there’ll be no doubt that kazcynski was right, that the technological system is a kind of mortal threat.”