Michael Buckley’s landmark intellectual history, At the Origins of Modern Atheism, proves that one can combine meticulous analysis and profound insight with a straightforward thesis. An overarching theme of the work is that atheism is produced by the (perceived or real) internal contradictions of theism, and thus takes its shape in response to theistic claims. In order to understand atheism, then, one must examine the theism it denies. Atheism is distinct in the modern period, because only in the modern period are there atheists. In the ancient and medieval worlds, atheism was a hypothetical position or a polemical insult; in the modern world, there is a group of people who recognize themselves as atheists and are proud to be labeled so.
True to his premise, Buckley traces the peculiar character of modern Western atheism to the choices made by theistic philosophers in the early modern era. At the turn of the 17th century, Leonard Lessius, a Flemish Jesuit, wrote De providentia numinis (On Divine Providence) to combat atheism. Yet his attacks are not against any modern atheist (they are apparently too shrewd to announce their unbelief openly) but against the classical figures associated with atheistic belief. As Lessius’ “atheists” are drawn from classical antiquity, so are his refuting arguments. This approach makes atheism primarily a philosophical, not a religious issue. Another Jesuit, Marin Mersenne, likewise sought to combat present atheism along classical lines. He too excuses faith, but designs an argument for god upon ancient Epicurean and Neoplatonic lines. In the distinction between faith and reason, the battle against atheism is conducted by reason in the method of philosophy. Jesus and traditional theology scarcely appear, and will continue to play only a token role through the Enlightenment.
The two most pivotal intellectual figures of the early modern period are René Descartes, the founder of a Universal Mathematics, and Isaac Newton, the founder of a Universal Mechanics. Both were theists, and both insisted that the existence of god could be defended by reason alone. Rather, reason is the only justifiable foundation for theistic belief. Yet, the two offer different approaches. Descartes’s skepticism argues not from the world to god but from god to the world. God is necessary as the guarantor of human reason, and then as the connection between the mind and the external world. Since we must be indubitably sure of god’s existence, and since indubitable knowledge must be gained by the geometrical method, there is no place (or need) for revelation or personal experience to establish god’s existence.
Newton, however, takes the physical world for granted, and seeks an explanation of its predictability and order. God appears as a necessary postulate for the Newtonian universe to function as it should. Absolute time and absolute space must be necessary effects of god’s existence. He must be the one who formed great astronomical masses and determined the correct distance of the planets from the sun to ensure stable orbits. Further, Newton’s calculations revealed that the universe is not quite self-sustaining; god must periodically wind the clock to keep it from getting too out of time.
Some theologians jumped on the chance to develop the Cartesian or Newtonian philosophies into even more rigorous proofs. Nicholas Malebranche, a French priest, pressed Cartesian dualism to the limit. Since mind and body are separate substances, all sensation must be due to the direct intervention of god. The soul and god are more closely united than the soul and the body. Our idea of god is the idea of the infinite, which is not really an idea at all but the direct presence of god in the human consciousness. Samuel Clarke, an English philosopher of unorthodox Christianity, sought a Newtonian path to god. He argued from the non-necessity of matter to a necessary being. Then, “necessity requires immensity and immensity requires omnipresence” (184). Likewise, an examination of intelligence in the world leads us to an intelligent cause.
Thus, the stage is set for the atheism of Denis Diderot. Diderot did not begin an atheist, and in fact earlier in his life wrote proofs from design and order for the existence of god. However, during his research into the intellectual formation of the blind, Diderot uncovered the dark side of the argument from order. Order is not the only characteristic of the universe; there is also disorder. If god is invoked to explain order, what can explain the disorder? Dualism was not an acceptable answer for Diderot or any other early modern philosopher. Instead, Diderot sought a single principle capable of explaining both: matter. If matter is to be the explanatory principle, however, it cannot be as Newton suggest, mere inert bulk to which motion is added extrinsically. Rather, following Democritus’ atomic theory, matter must be imbued with its own motion and potentiality. As a seed contains within itself the entire organism which will follow, so all matter contains within itself its own dynamic principles, eternally in motion. Life can thus come from non-life through recombination, and the intelligible world can be understood as a higher echelon of development in matter.
Baron Paul Henri d’Holbach extended Diderot’s line of argumentation and systematized an atheist polemic against theistic belief in his groundbreaking work, Le Système de la nature ou des loix du monde physique et du monde moral (The System of Nature or the Laws of the Physical World and the Moral World). From the title one gleans d’Holbach’s proposition: nature, sufficiently examined and systematized, suffices to explain both physics and morals. The supernatural is reduced entirely to the natural. “Motion as a result or inherent attribute of matter gives natural philosophy its own enclosed world, its own principle, and eliminates the natural theologies of either the religious believer or the deist. Matter carries the attributes of god. It is the necessary being. It is contradictory, inconceivable, to imagine a moment when it did not exist. And since motion is a necessary property of matter, it is coeval with matter” (282).
As Diderot had explained both order and disorder by a single principle, d’Holbach explained both atheism and religious belief by the single principle of nature. At the heart of human motivation is a single principle, self-conservation. Pain and fear—and the corresponding impulse to avoid them—explain every human action, invention, and belief. Some people handle their pain and fear by philosophic investigation, allowing them more control over them environment. Others turn to religious hypotheses, soothing themselves by thinking that the deities can be rendered propitious by a certain type of living. In d’Holbach’s reading, religious belief is caused by ignorance of nature, so he predicted that advancing scientific progress was destined to destroy religion. The common argument for god by appeal to universal human worship is refuted by pointing out the great variety of beliefs between cultures. There is no single concept of god underlying all of them.
At the end of the Enlightenment, the grounds for both theism and atheism had shifted. Kant’s critique had rendered Cartesian rationalism impotent. Laplace’s corrected Newtonian equations left no need for god to interfere with the operation of the cosmos. Schleiermacher’s existential defense of religion changed the grounds of the debate; atheism, as is its habit, adapted and followed suit. Theistic arguments continue to be formed and deconstructed.
Among the lessons Buckley draws from his investigation, two stand out for special consideration:
“The Christian god cannot have a more fundamental witness than Jesus Christ, even antecedent to the commitments of faith; Christian theology cannot abstract from Christology in order to shift the challenge for this foundational warrant onto philosophy. Within the context of a Christology and a Pneumatology of both communal and personal religious experience, one can locate and give its own philosophical integrity to metaphysics, but Christology and Pneumatology are fundamental. If one abrogates this evidence, one abrogates this god” (361).
“If an antimony is posed between nature or human nature and god, the glory of one in conflict with the glory of the other, this alienation will eventually be resolved in favor of the natural and the human. Any implicit, unspoken enmity between god and creation will issue in atheism” (363).