In existographies, Baron d’Holbach (1723-1789) (IQ:190|#31) [RGM:414|1,500+] [SN:12] (FA:74) (GAE:1) (GPhE:5) [CR:251], born Paul Dietrich, aka Paul-Henri Thiry, "Jean-Baptiste de Mirabaud" (pseudonym), or the "materialist Mirabaud" (Owen, 1829), was a German-born French-raised atheism-explicit anti-chance based matter-and-motion philosopher, noted for his Holbach’s school (Ѻ), Holbach's geometrician (forerunner to Laplace's demon), etc., characterized as the “Newton of the atheists” (Ѻ)(V|1:45) or "the supreme materialist" (Cooper, 1976), even cited so in history of atheism documentaries, and high ranked extreme atheist, who; in epicenter genius categorizations, was “one member of Voltaire’s circle”, if not the leader, and who; according to Caspar Hakfoort, was one of the stepping stone pioneers of scientism, being generally known for his 1770 The System of Nature: the Laws of Moral and Physical World, referred to by some as an "Atheist’s Bible", wherein saw the universe as nothing more than matter in motion, bound by inexorable natural laws of cause and effect, in which there is “no necessity to have recourse to supernatural powers to account for the formation of things.” 
Holbach was said to have been “abandoned by his parents and raised by his uncle, for whom he had no particular affection” (Ѻ) or his “mother died leaving him an orphan at a young age” (Ѻ) or “his father, a rich parvenu, according to Rousseau, died when Holbach was still a young man, after his father had brought him to Paris at age 12” (Ѻ) or “was apparently an orphan by the age of 13 and lived with his uncle (from whom he took the new name Holbach)” (Ѻ).
In 1753, Holbach's father and uncle both died (deboundstated), leaving him an immense fortune, with which he used to fund his famous intellectual salons. 
Solon | Meetings
See also: Hume-Holbach dinner partyHolbach, for thirty years, from 1750 to 1780, at his second mansion Le Château de Grand-Val, outside of Paris, ran a bi-weekly intellectual salon, with the entice of excellent food, expensive wine, and a library of over 3000 volumes, he attracted many notable visitors, including: Diderot, Grimm, Condillac, Condorcet, D'Alembert, Marmontel, Turgot, La Condamine, Helvetius, Jean-Jacques Rousseau, Adam Smith, David Hume, and Benjamin Franklin.
Holbach's was keen on Lucretius, e.g. his children's tutor had published a new translation of On the Nature of Things. Holbach read Jean Meslier, John Toland, Anthony Collins, Denis Diderot, when he edited Holbach's System of Nature, added footnotes of doubters from Cicero to Thomas Hobbes.
System of Nature
See main: The System of NatureIn circa 1768, d'Holbach finished a draft of his The System of Nature: the Laws of Moral and Physical World. He showed the draft to Denis Diderot who complained privately, to someone, the following, as summarized by Scott:
“There was no wit, no shadow, no nuance, no multi-sidedness, no art, no pleasure or erotic play to be found in its pages. It denied god, argued that all religions were created out of fear, ignorance, and anthropism; that souls did not outlive the body; that the world was determined by strict laws.”
Diderot went on to admit to friends that d’Holbach made “atheism dull”, and that his book was an act of war—to destroy the power of religion, via reference to the new sciences.
In 1770, d'Holbach, after smuggling it across the border into Amsterdam to be published, under a pseudonym (Ѻ), under the name "Jean-Baptiste de Mirabaud", e.g. see the 1795 English translation by William Hodgson (Ѻ), then shipped it back to France, where it debuted anonymously as The System of Nature, soon-to-be-dubbed (Ѻ)(Ѻ) the “Atheist’s Bible”, to the public. The anonymous work, of note, was initially attributed to Helvetius and Honore Mirabeau. 
Critical History of Jesus Christ
In 1770, d’Holbach published Critical History of Jesus Christ: a Rational Analysis of the Gospels, oft-cited as one of the first Christ myth theory books, wherein he attempted to debunk the authenticity of Jesus Christ; the following are noted sections: 
“The salvation of Christians thus depends neither on the reading nor on the understanding of the sacred books, but on the belief that these books are divine. If, unfortunately, the reading or examination of any one, does not coincide with the decisions, interpretations, and commentaries of the church, he is in danger of being ruined, and of incurring eternal damnation. To read the gospel, he must commence with being disposed blindly to believe all which that book contains; to examine the gospel, he must be previously resolved to find nothing there but the holy and the adorable; in fine, to understand the gospel, he must entertain a fixed persuasion, that the priests can never be themselves deceived, or wish to deceive others in the manner they explain it. "Believe, (say they,) believe on our words that this book is the work of God himself; if you dare to doubt it, you shall be damned. Are you unable to comprehend anything which God reveals to you there? Believe evermore: God has revealed himself that he may not be understood.”
— Baron d’Holbach (1770), Critical History of Jesus Christ (pg. 6)
“Victor of Tunis informs us, that, in the sixth century, the Emperor Anastasius "caused the gospels to be corrected, as works composed by fools." The Elements of Euclid are intelligible to all who endeavor to understand them; they excite no dispute among geometricians. Is it so with the Bible? and do its revealed truths occasion no disputes among divines? By what fatality have writings revealed by God himself still need of commentaries? and why do they demand additional lights from on high, before they can be believed or understood? Is it not astonishing, that what was intended as a guide to mankind, should be wholly above their comprehension? Is it not cruel, that what is of most importance to them, should be least known?”
— Baron d’Holbach (1770), Critical History of Jesus Christ (pg. 9)
“It is also extremely difficult to ascertain whether those books belong to the authors whose names they bear. In the first ages of Christianity there was a great number of gospels, different from one another, and composed for the use of different churches and different sects of Christians. The truth of this has been confessed by ecclesiastical historians of the greatest credit. (Tillemont, tom. ii. 47, etc. Epiphan. Homil. 84. Dodwell's Disser. on Irenaeus, p. 66. Freret's Examin. Critique. Codex Apocryphus, &c.) There is, therefore, reason to suspect, that the persons who composed the acknowledged gospels might, with the view of giving them more weight, have attributed them to apostles, or disciples, who actually had no share in them. That idea, once adopted by ignorant and credulous christians, might be transmitted from age to age, and pass at last for certainty, in times when it was no longer possible to ascertain the authors or the facts related. Among some fifty gospels, with which Christianity in its commencement was inundated, the church, assembled in council at Nice [325AD], chose four of them, and rejected the rest as apocryphal, although the latter had nothing more ridiculous in them than those which were admitted. Thus, at the end of three centuries, (i.e. in the three hundred and twenty-fifth year of the Christian era,) some bishops decided, that these four gospels were the only ones which ought to be adopted, or which had been inspired by the Holy Spirit. A miracle enabled them to discover this important truth, so difficult to be discerned at a time even then not very remote from that of the apostles.”
— Baron d’Holbach (1770), Critical History of Jesus Christ (pgs. 10-11)
“Notwithstanding this decision, there still remain some difficulties on the authenticity of the gospels. In the first place, it may be asked whether the decision of the Council of Nice, composed of three hundred and eighteen bishops, ought to be regarded as that of the universal church? Were all who formed that assembly entirely of the same opinion? Were, there no disputes among these men inspired by the Holy Spirit? Was their decision unanimously accepted? Had not the authority of Constantine a chief share in the adoption of the decrees of that celebrated council? In this case, was it not the imperial power, rather than the spiritual authority, which decided the authenticity of the gospels?”
— Baron d’Holbach (1770), Critical History of Jesus Christ (pgs. 12)
The gist of this, up to this point, seems to be the conjecture that that Christianity was invented in 325AD, under the orders of Roman Emperor Constantine I, during which time 318 bishops, following debate and discussion, picked four (Matthew, Mark, Luke, John) of 50 total potential gospels, to the be the core of the new religion of the empire.
In 1772, d’Holbach published Common Sense (Bon Sens), under the pseudonym of "Cure Meslier", a work said to be deeply indebted to Meslier, which gave a popular expression to the former’s atheism; by 1803, it was recognized that the work had been written by Holbach. 
Soul | Determinism
On the determinism and the soul, religiously conceptualized as an autonomous entity, d'Holbach, in his “A Defense of Determinism” (Ѻ), had the following to say:
“Those who have affirmed that the soul is distinguished from the body, is immaterial, draws its ideas from its own peculiar source, acts by its own energies, without the aid of any exterior object, have, by a consequence of their own system, enfranchised [liberated] it from those physical laws according to which all beings of which we have a knowledge are obliged to act. They have believed that the soul is mistress of its own conduct, is able to regulate its own peculiar operations, has the faculty to determine its will by its own natural energy; in a word, they have pretended that man is a free agent.”
Holbach attended Leiden University from 1744 to 1748. In c.1759, Holbach translated the best works published by the Germans on natural history and chemistry into French. 
Quotes | Employed
The following are quotes employed by Holbach:
“Timaeus of Locris (Ѻ), who was a Pythagorean, admits that the doctrine of future punishments was fabulous, solely destined for the imbecility of the uninformed, and but little calculated for those who cultivate their reason.”
— Baron d’Holbach (editor) (1770), The System of Nature (pg. 129)
“We believe that that which is will always be, and that the same causes will have the same effect.”
— Thomas Hobbes (1655), a paraphrase, supposedly (Joshi, 2014), his chapter on causality in De Corpore; cited by Baron d’Holbach (1770) in System of Nature (pg. 124)
Quotes | On
The following are noted quotes on Holbach:
“I have never met with a man more learned—I may add, more universally learned, than the Baron d'Holbach; and I have never seen anyone who cared so little to pass for learned in the eyes of the world. Had it not been for the sincere interest he took in the progress of science, and a longing to impart to others what he thought might be useful to them, the world would always have remained ignorant of his vast erudition. His learning, like his fortune, he gave away, but never crouched to public opinion. The French nation is indebted to d'Holbach for its rapid progress in natural history and chemistry. It was he who, 30 years ago, translated (enriched with valuable notes) the best works published by the Germans on both these sciences, till then, scarcely known, or at least, very much neglected in France. Holbach possessed an extensive library, and the tenacity of his memory was such as to enable him to remember without effort every thing he had once read ”
— Friedrich Melchior (1789), “On Baron d’Holbach”, Aug 10; note that, in the context of this quote, Melchior (Ѻ) was also closely associated with: Jean Rousseau (IQ:175|#243), Denis Diderot (IQ:175|#243), Jean d'Alembert (IQ:185|#73), Marmontel, Morellet, and Helvetius (IQ:175|#215) 
“There is no book of atheistical description which has made a greater impression than the famous System of Nature.”
— Henry Brougham (c.1856) (Ѻ) 
“The failure of the reformation to capture France had left for the Frenchmen no half-way house between infallibility and infidelity; and while the intellect of Germany and England moved leisurely in the lines of religious evolution, the mind of France leaped from the hot faith which had massacred the Huguenots to cold hostility with which La Mettrie, Helvetius, Holbach, and Diderot turned upon the religion of the fathers.”
— Will Durant (1926), the Story of Philosophy 
“The notion that the brain itself feels and thinks is a ‘revolting opinion’ reminiscent of the ‘insane [see: crazy] author [Holbach] of the Systéme de la Nature’.”
— Mathieu Buisson (c.1802) (Ѻ), as cited by L.S. Jacyna (1987) in summary of Buisson’s criticism (Ѻ)(Ѻ) of Xavier Bichat’s 1801 theory (Ѻ) of physiological properties; note: quoted misattributed, by Jennifer Hecht (2003), to Louis de Bonald
“Nietzsche launched a new building project that represents an advance for atheism. Meslier denied all divinity, Holbach dismantled Christianity, Feuerbach deconstructed god. Then Nietzsche introduced transvaluation: atheism is not an end in itself. Do away with god, yes, but then what? Another morality, a new ethic, values never before thought of because unthinkable, this innovation is what makes it possible to arrive at atheism and to surpass it. A formidable task, and one still to be brought to fruition.”
— Michel Onfray (2005), Atheist Manifesto (Ѻ)
“As Casper showed in his article ‘The Historiography of Scientism: A Critical Review’ (1995), the notion of scientism in a variety of meanings has been around for a long time; still, Casper put it to new uses by applying it to persistent efforts over the centuries, from Hobbes and d’Holbach to Capra and Hawking in our own day, to make the latest science serve the construction of a world-view.”
— Floris Cohen (2009), “Note about an Unfinished Book on Ostwald by the Late Casper Hakfoort” 
“As romantic genius will claim, geniuses help move history forward. Their voices speak to the future, as Stael explains in all her comments on genius. Or, as Baron d'Holbach said of his fellow philo-sophes: ‘You are not men of your times; you are men of the future, the precursors of future reason. It is not wealth, nor honour, nor vulgar applause that you should aim for, it is immortality.’ The genius advances progress by his discoveries, ‘soaring like an eagle toward a luminous truth’, as the essay on genius in the Encyclopedie explained.”
— Kathleen Kete (2012), Making Way for Genius: the Irish Aristocracy in the Seventeenth Century 
“D’Holbach’s book caused a great stir among the Paris savants, effectively dividing the deists from the atheists. Voltaire, committed to deism and long impatient with d’Holbach’s declamatory ways, called it ‘a chaos, a great moral sickness, a work of darkness, a sin against nature, a system of folly and ignorance.’ He wrote to Delisle de Sales: “I think that nothing has debased our century more than this enormous stupidity.”
— Rebecca Stott (2013), Darwin’s Ghosts: in Search of the First Evolutionists 
“Holbach’s treatise [System of Nature] remains one of the most exhaustive discussions of atheism — from a scientific, philosophical, moral, and political perspective — ever written.”
— Sunand Joshi (2014), The Original Atheists 
“Baron d’Holbach is first modern atheist in Western Christian tradition; the first intellectual since antiquity to really make a case for atheism, that wasn’t just an attack on Christianity.”
— Chad Denton (2017), “A Century of Lights, Episode 8” (V|6:13-23), Jan 26
Quotes | By
The following are notable quotes by Holbach:
“An so, wise men, you are not men of your times; you are men of the future, the precursors of future reason. It is not wealth, nor honour, nor vulgar applause that you should aim for: it is immortality.”
— Baron d’Holbach (1770), Essay on the Prejudices (see: posthumous genius) 
“To discover the true principles of morality, men have no need of theology, of revelation, or of god.”
— Baron d’Holbach (c.1770) (Ѻ)
“All children are born atheists; they have no idea of god.”
— Baron d’Holbach (1772), Freethoughts Opposed to Supernatural Ideas 
1. (a) d’Holbach, Baron. (1770). The System of Nature: or the Laws of Moral and Physical World, Volume 1 (pg. 25). London, 1797.
(b) d’Holbach, Baron. (1770). The System of Nature: Laws of the Moral and Physical World (notes by Denis Diderot; translator: H.D. Robinson). J.P. Mendum, 1889.
2. (a) Durant, Will. (1926). The Story of Philosophy (pg. 175). Simon & Schuster, 1953.
(b) Hsieh, Ching-Yao, and Ye, Meng-Hua. (1991). Economics, Philosophy, and Physics (pgs. 13-14). M.E. Sharpe.
3. Cohen, H. Floris. (2009). “Note about an Unfinished Book on Ostwald by the Late Casper Hakfoort, and About Its Author” (pdf), hp4all.nl.
4. d’Holbach, Baron. (1772). Good Sense without God: or Freethoughts Opposed to Supernatural Ideas (Ѻ). Amsterdam.
5. Scott, Rebecca. (2013). Darwin’s Ghosts: in Search of the First Evolutionists (Voltaire, pg. 157). A&C Black.
6. (a) Berman, David. (2007). “Unbelief during the Enlightenment”, in: The New Encyclopedia of Unbelief (editor: Tom Flynn; foreword: Richard Dawkins) (§:276-80, esp. pg. 277). Prometheus Books.
(b) Meslier, Jean. (1729). Testament: Memoir of the Thoughts and Sentiments of Jean Meslier (translator: Michael Shreve; preface: Michel Onfray) (pg. 25). Prometheus Books.
7. d’Holbach, Baron. (1770). Ecce Homo [Behold the Man]: a Critical Inquiry into the History of Jesus of Nazareth, Being a Rational Analysis of the Gospels [Critical History of Jesus Christ: a Rational Analysis of the Gospels] (Histoire critique de Jésus-Christ, ou Analyse raisonnée des Évangiles) (Gut)(txt). Gordon Press, 1977.
8. (a) Gaskin, J.C.A. (1989). Varieties of Unbelief: from Epicurus to Sartre (pg. 92). Prentice-Hall.
(b) Hecht, Jennifer M. (2003). Doubt: A History: The Great Doubters and Their Legacy of Innovation from Socrates and Jesus to Thomas (pg. 353). HarperOne.
9. Joshi, Sunand T. (2014). The Original Atheists: First Thoughts on Nonbelief (pg. 71). Prometheus Books.
10. d’Holbach, Baron. (1770). The System of Nature: Laws of the Moral and Physical World (notes by Denis Diderot; translator: H.D. Robinson) (attributed, pgs. iv-v; universally learned, pg. v; translated, pg. v). J.P. Mendum, 1889.
11. (a) Holbach, Baron. (1770). Essay on the Prejudices: Of the Influence of the Opinions on the Manners and the Happiness of Man (Essai sur les préjugés: ou, De l'influence des opinions sur les moeurs et sur le bonbeur des Hommes ) (§14). Publisher.
(b) Naville, Pierre. (1967). D’Holbach et la philosophie scientifique au XVIIIe siècle (pg. 359-60). Gallimard.
(b) Taylor, Charles. (1992). The Sources of the Self: the Making of the Modern Identity (pg. 353). Cambridge University Press.
(c) Kete, Kathleen. (2012). Making Way for Genius: the Irish Aristocracy in the Seventeenth Century (pg. #). Yale University Press.
● Holbach, Baron. (1761). Christianity Unveiled: an Examination of the Principles and Effects of the Christian Religion (translator: W.M. Johnson). Translator, 1835.
● Holbach, Baron. (1761). Christianity Unveiled (translator: David Holohan). Publisher, 2008.
● Holbach, Baron. (1768). Letters to Eugenia: a Preservative Against Religious Prejudices (Preface: Jacques Naigeon) (translator: Anthony Middleton) (Ѻ). Mendum, 1870.
● Holbach, Baron. (1772). Common Sense: Natural Ideas Opposed to Supernatural. Publisher.
● Holbach, Baron. (1773). Social System. Publisher.
● Holbach, Baron. (1776). Universal Morality. Publisher.
● Baron d’Holbach – Wikipedia.
● The System of Nature – Wikipedia.