This work by Karl Marx is his Doctoral Thesis. It goes right to the heart of the dichotomy between first the magical thinking that humanity has plagued man's reasoning and been used to oppress humanity, and then the secular, scientific, and rational thinking that has bloomed from the writings of Epicurus, Lucretius and a watershed of others that unfold as the hallmarks of the modern world. It argues for this new direct observation-based Epicurean method as a new development rather than as a mere revision of Democritean thinking which relied more on distilling The only rule which Epicurus prescribes, namely, that “the explanation should not contradict sensation", is self-evident; for to be abstractly possible consists precisely in being free from contradiction, which therefore must be avoided. Our modern world is still troubled because out society as a whole still doesn't acknowledge the difference between: 1) the magical fate of Democritus pulling us forward to some fore-drawn conclusion that tugs on the atoms, and... 2) the natural forces of Epicurus who sees us riding the wave of the chain of causation of the interaction of atoms and consider the specific situations of judgement and action that we can empower ourselves with. One thing that caught me off guard was how Marx referenced portrayals of Epicurus seeing himself as dogmatic. His only dogma though, as stated above, is that we not assert in contradiction to what we observe. For me this was a significant idea, and identifies one of the key boundaries that Karl Popper later points out as a critique of Marx's own work. That we should not base our actions on things unfalsifiable, that cannot be observed or confirmed because of the structure of the assertion (like "there is an imaginary friend that controls everything that you will not be able to see because he is super-powerful ". Epicurus, and Popper both suggest we must frame our assertions so that we live in the humility of confirmation. This view in Marx's thesis here is actually quite close to Popper. Democritus was on the other hand one for not trusting our observations, and for instead looking for coherence merely in metaphysical structure as the true meaning. This is likely because, as the quotes suggest about Democritus, he relied on the clerical(and spiritualist) communities of Egypt, Babylon, and other places for his framework of ideas and not a direct examination of nature itself. This assertion that Democritus relied on spiritualist intellectual communities, while likely is tenuous. I would hope that the vast recent uncovering and deciphering of ancient writings from the time of Democritus and back deep into the bronze age could yield a better understanding of the cultures to which he traveled. In Popper's work, "The Open Society And It's Enemies" he suggests that although Marx was well-meaning and humanitarian, that he was influenced by Hegel, and thus through Plato engaged in abstractions as the higher truths, as though they were more sure than direct observations. Yet this thesis opened my eyes to Marx's early struggles with these problems, and with his well thought out investigation into the very dividing line that Popper is concerned with. It makes me think that Popper was unaware of this work. Despite this, Popper's work is indeed important, and he does point out significant flaws with Marx's later works. One thing that surprised me about this work is the use of Cicero, Simplicicus, and Plato who often speak in denial and disparagingly. Fortunately, he also goes on to rely on Lucretius, which is a more direct line within the Epicurean tradition and a more coherent presentation of the ideas in general. Fortunately, Marx reads through the negative commentaries also to find the excellent assertions which they ridicule. Because of this extended investigation, Marx is well placed as an atomic theorist, and is part of the chain that led us to the modern understanding of the atom, and thereby modern science including physics, physics-integrated chemistry, and physics-integrated biology. In Epicurus, Marx also witnesses one of the most forceful arguments that sterilizes the world of spiritual and metaphysical conjecture. His metaphors of atoms swerving of their own nature is extended to humans needing no cause but their own desire to avoid pain in order to develop ethics, and gods avoiding the humans by swerving from confusion and thus being wholly unengaged rather than holy terrors. This research surely must have influenced Marx later insistence that we find our humaneness, or justifications for how we treat each other, and our moral obligations in the real world, in the natural world in which we share our conversations and our lives. And it is for Epicurus' observations about our autonomy, and the absence of any spiritual meaning, that he has been ridiculed and banned down through the ages from the vitrolic of St. Augustine and the Spiritualist Cicero to the modern day. It is no wonder that those supported by assertions of "spiritual authority" have seen science and rational thinking attacked in an endless stream of "pious" indignation since we first started clearly describing the world that no longer needed spiritual destinations to have sound ethics and social authority. Once Marx digested this perspective, his views of the religious institutions of Europe must have changed. It is important to realize that Marx's investigation is in the differences between Epicurus and Democritus, and does not involve any physical examination of atoms or sociological studies at this point of populations. Yet we do see experimental action being taken on these earlier observations. The experimental tradition was alive though in Galileo, Boyle, Newton, Mendeleev, and Bor as Lucretius would bid us do. What Marx does is uncover though is the constant barrage of mischaracterizations that spiritualists have used to dismiss a the pragmatic and observation oriented approach that Epicurus brought to the quest for understanding and happiness. At it's root, Eicurus' idea of the phsyical atom undercut a range of metaphysical ideas from Plato's forms, and essences, to deities or spiritual energy that intervene and the soul. Scientists are still doing those things today as they debunk nonfalsifiable claims and pseudo science in each generation. In ethical terms, it means, according to Epicurus, that this world, the natural world of real qualities and sensuousness, is the one to value, and that others imagined are only tangents and not the underlying truth. Marx does not however go quite this boldly in this portrayal. Time, is also dealt with in a pragmatic fashion by Epicurus, and Marx clarifies its different treatment from Democritus as highly significant. For Epicurus, time is perhaps "reality appearing", perhaps unfolding and as we perceive through our senses, that sensing is what we understand time to be. For Democritus, time is something that can be dismissed as illusory, and not necessary for atoms, much like western religious concepts of eternity. While Epicurus' and Democritus' attempt to explain hearing and vision was a rather abstract description, it appears to be left to the material world. Marx concedes the similarity here. But Marx concludes his section on time with the following statement, "Hence the senses are the only criteria in concrete nature, just as abstract reason is the only criterion in the world of the atoms." Concerning heavenly bodies, Marx demonstrates the sharp difference of Epicurus' views not only to Democritus, but to the bulk of Greek society. For Epicurus, the celestial world is bound by the same general rules as the terrestrial, and not magical forces to which we must either bow or aspire, but more independent versions of nature with the same qualities. While Marx points out that Epicurus acknowledged some contradictions here, even that is an important part of philosophy. Based on the unique characteristics of Epicurean philosophy identified and analyzed by Marx, the conclusion is an acknowledgement that these unique qualities are the one he contributed in the context of the Greek Enlightenment that spawned the scientific movement, thus earning the praise of not only Lucretius in that time, but of us now in the face of the development of science through the Renaissance, the Enlightenment, and the modern scientific revolution. The Appendix is also worthwhile in that Marx defends Epicurus from the attack of Plutarch. This Appendix also includes argument that the “proofs for the existence and need for god” are frivolous and generally the first place you can go to confirm the non existence of any god, by the very definitions forwarded. https://books.google.com/books?id=49P... https://marxists.anu.edu.au/archive/m...