Without a doubt, the Marxists were largely correct in seeing the basic struggle16 in ancient Greek thought as that between lonian (dialectical) materialism17 and Athenian (Socratic) idealism,18 and gave a tolerable account of the views of especially the former in general and Heraclitus19 and Democritus20 and Epicurus21 in particular.
Marxists are also largely correct in their claim that mediaeval Christianity became synthesized with Greek thought,22 that the Roman Catholic Church was the great unifying factor behind feudalism,23 that philosophy was then reduced to the status of a "handmaid of theology,"24 that some mediaeval anti-Catholic sects25 sought to implement communal property instead of the private property which early26 and Augustinian27 Christianity had defended, and that three camps then strove for the ascendancy~the essentially reactionary Roman Catholics, the essentially revolutionary communistic Anabaptists, and the essentially reformist Protestant Lutherans.28
Communists are, in our opinion, also correct in tracing the rise of the Renaissance in the arts and sciences to the left wing of the Catholic camp,29 and the heart of the Reformation and its free enterprise economic and natural scientific consequences to the doctrine of John Calvin as a consequence of his predestinarian teachings.30
Again, we cannot but agree with the main thrust of the Marxist view of the relation between de-Christianized natural science and the growth of deism31 and the deistically inclined men of the later Renaissance and the growth of the essentially communistic utopias of that time.32
Essentially correct too is the Marxist view that especially Descartes should be regarded as the father both of modern naturalism and of modern rationalism,33 and that the views of Gassendi,34 Hobbes,35 Spinoza,36 and Newton37 led to the development of full-fledged deism and, via Locke,38 Bayle,39 and Priestley,40 and via the German Enlightenment of Leibniz41 and Kant,41a ultimately developed into the humanistic French Enlightenment42 of Meslier,42 La Mettrie,43 Diderot,44 Morelly,45 Rousseau,45 Helvetius,46 Voltaire,46 Mably,47 D'Holbach,47a and, finally, the French Revolution.48
Nor can it be denied that precisely this French Revolution – which, as the Marxists correctly pointed out, followed on the economic miseries of the poor in the first stages of the contemporaneous Industrial Revolution49 –had long been threatening as a result of the doctrines of the French Enlightenment in general50 and the communists Meslier,42 Morelly,45 and Mably47 in particular and as a result of the activity of revolutionary communist groups like the Russian Pugachevians, the Bavarian Illuminati,51 and, finally, the French Revolutionary Jacobins52 and the communistic Babouvians.53
Again, the Marxist account of the dialectical nexus between the nineteentli-century dialectical idealist Hegel and the ancient Greek materialistic dialeetician Heraclitus, and the Marxist account of their own transposition of Hegelian dialectical idealism via the materialistic left-Hegelianism of Feuerbach into Marxian dialectical materialism is essentially correct,54 as too is the Marxist contention that it was precisely the utopian socialism.55 of St. Simon and Fourier-itself doubtless56 the product of the French Revolution-that was translated into the "scientific socialism"57 of Marx and Engels, whose Manifesto of the Communist Party58 indeed clearly evidences the large extent to which its authors drew on the French Revolution and on later Babouvian communism and utopian socialism as Marxism's own socialistic predecessors.59
The statements of Engels (that "we German socialists . . are derived not only from St. Simon, Fourier and Owen, but also from Kant, Fichte, and Hegel")60 and of Lenin (that "Marx's dialectic was taken from Hegelian German philosophy, his economics from the classical British school, and his radical politics from the French Revolution,"61 and that "the doctrine of Marx . . . is the legitimate successor of . . . German philosophy, English political economy and French Soeialism")62 are thereafter largely correct. For it was the materialist Ludwig Feuerbach who converted Marx and Engels to dialectical materialism,63 and the socialist Moses Hess who converted them to communism,64 and Marx and Engels themselves who combined the two into Marxian socialism.65