“The Industrial Revolution and its consequences have been a disaster for the human race. They have greatly increased the life-expectancy of those of us who live in ‘advanced’ countries, but they have destabilized society, have made life unfulfilling, have subjected human beings to indignities, have led to widespread psychological suffering (in the Third World to physical suffering as well) and have inflicted severe damage on the natural world. The continued development of technology will worsen the situation. It will certainly subject human beings to greater indignities and inflict greater damage on the natural world, it will probably lead to greater social disruption and psychological suffering, and it may lead to increased physical suffering even in ‘advanced’ countries.” 
Ted Kaczynski is and was a brilliant man, and my criticisms of his manifesto are countervailed by respect for him as my intellectual superior. I will attack the heart of his thesis as an expression of that respect, rather than picking away at secondary issues or quibbles. An example of such a secondary issue that I argued in a different essay is that Kaczynski’s focus on individual maladaptiveness is a red herring from the more encompassing multi-level selection model of evolutionary psychology. However, his more important mistake is to assume a moral ontology based on negative utilitarianism, and to assume that his audience shares this assumption, and proceed to commit the naturalistic fallacy repeatedly. A paragraph under the heading Human Suffering demonstrates Kaczynski’s dependence on this moral framework in microcosm:
“In the third place, it is not at all certain that survival of the system will lead to less suffering than breakdown of the system would. The system has already caused, and is continuing to cause, immense suffering all over the world. Ancient cultures, that for hundreds of years gave people a satisfactory relationship with each other and with their environment, have been shattered by contact with industrial society, and the result has been a whole catalogue of economic, environmental, social and psychological problems. One of the effects of the intrusion of industrial society has been that over much of the world traditional controls on population have been thrown out of balance. Hence the population explosion, with all that that implies. Then there is the psychological suffering that is widespread throughout the supposedly fortunate countries of the West (see paragraphs 44, 45).” 
Negative utilitarianism posits that moral people ought to act so as to minimize suffering . However, many religious traditions have disagreed with this assumption and it is not clearly and obviously true. For example, in the Bhagavad Gita Krishna instructs Arjuna to increase human suffering because failure to do his duty as a warrior would compromise the divine order, which would be a greater evil than human suffering. The Flagellant sects of 14th century Europe serve as a more concrete example. And I certainly don’t agree with the premise myself, as there appears to be an Aristotelian mean of suffering to produce Christian growth toward godliness that is almost always higher than the amount we’d prefer by nature.
Kaczynski relies on negative utilitarianism throughout his manifesto. While his whole essay can’t be reduced to the statement “We are morally compelled to reduce suffering if we can,” I believe any reasonable reader will agree with my assertion that most of his arguments would fall apart if the statement were false. At the risk of oversimplifying, I’d reduce the bulk of his manifesto to the enthymeme:
1. (Implicit, assumed) We ought to reduce suffering if we can.
2. Technology causes suffering.
3. We ought to reduce technology so that it causes less suffering.
This draws an “ought” conclusion from an “is” premise, while leaving the “ought” premise implicit and therefore unexamined and unchallenged. This is an example of the naturalistic fallacy (NB: distinct from “appeal to nature”).
 T. Kaczynski, “Industrial Society And its Future,” The Washington Post, 19-Sep-1995.
 “Utilitarianism,” Encyclopædia Britannica. [Online]. Available: https://www.britannica.com/topic/utilitarianism-philosophy. [Accessed: 24-Nov-2021].