“Before the eighteenth century the demographic impact of the profession of medicine remained negligible. Relatively few persons could afford to pay a doctor for his often very expensive services; and for every case in which the doctor's attendance really made a difference between life and death, there were other instances in which even the best available professional services made little difference to the course of the disease, or actually hindered recovery. …Only with the eighteenth century did the situation begin to change; and it was not until after 1850 or so that the practice of medicine and the organization of medical services begin to make large-scale differences in human survival rates and population growth.”

The Silence of the Body: Materials for the Study of Medicine (II silenzio del corpo: Materiali per studio di medicina, 1979), translated by Michael Moore, in The Body in the Library: A Literary Anthology of Modern Medicine, London and New York: Verso, 2003, p. 296 https://books.google.it/books?id=iFRwpEpgCKUC&pg=PA296.

Source: V. (1963), Chapter Ten, Part II
Context: In the eighteenth century it was often convenient to regard man as a clockwork automaton. In the nineteenth century, with Newtonian physics pretty well assimilated and a lot of work in thermodynamics going on, man was looked on as a heat engine, about 40 per cent efficient. Now in the twentieth century, with nuclear and subatomic physics a going thing, man had become something which absorbs X-rays, gamma rays and neutrons.

Les médecins administrent des médicaments dont ils savent très peu, à des malades dont ils savent moins, pour guérir des maladies dont ils ne savent rien.
This attribution to Voltaire appears in Strauss' Familiar Medical Quotations (1968), p. 394, and in publications as early as 1956 http://books.google.pt/books?id=lCtCAQAAIAAJ&q=%22Doctors+are+men+who+prescribe+medicine+of%22&dq=%22Doctors+are+men+who+prescribe+medicine+of%22&hl=pt-PT&sa=X&ei=mbnWUsvDIfTB7Aaw_YD4Dw&redir_esc=y; the quotation in French does not, however, appear to be original, and is probably a relatively modern invention, only quoted in recent (21st century) published works, which attribute it to "Voltaire" without citing any source.
Attributed

Source: Seven Great Statesmen in the Warfare of Humanity with Unreason (1915), p. 167
Context: The French philosophy of the eighteenth century was in full strength. Those were the years in which Voltaire ruled European opinion, and Turgot could not but take account of his influence. Yet no one could apparently be more unlike those who were especially named as the French philosophers of the eighteenth century. He remained reverential; he was never blasphemous, never blatant; he was careful to avoid giving needless pain or arousing fruitless discussion; and, while the tendency of his whole thinking was evidently removing him from the orthodoxy of the Church, his was a broader and deeper philosophy than that which was then dominant.

This attribution to Voltaire appears in Strauss' Familiar Medical Quotations (1968), p. 394, and in publications as early as 1956 http://books.google.pt/books?id=lCtCAQAAIAAJ&q=%22Doctors+are+men+who+prescribe+medicine+of%22&dq=%22Doctors+are+men+who+prescribe+medicine+of%22&hl=pt-PT&sa=X&ei=mbnWUsvDIfTB7Aaw_YD4Dw&redir_esc=y; the quotation in French does not, however, appear to be original, and is probably a relatively modern invention, only quoted in recent (21st century) published works, which attribute it to "Voltaire" without citing any source.
Original: (fr) Les médecins administrent des médicaments dont ils savent très peu, à des malades dont ils savent moins, pour guérir des maladies dont ils ne savent rien.

Source: Culture series, Inversions (1998), Chapter 7 (pp. 125-126)

Source: Part II : Practical Pictorial Photography, Fidelity to nature and justifiable untruth, p. 21

Ibid.
1890s

History Of The Freedom Movement In India Vol. 1 https://archive.org/stream/history1_201708/History+of+the+Freedom+Movement+in+India+Vol+1+-+RC+Majumdar_djvu.txt quoted from Elst, Koenraad (2014). Decolonizing the Hindu mind: Ideological development of Hindu revivalism. New Delhi: Rupa. p. 310-311