In his novel Arrowsmith Sinclair Lewis (1885-1951) portrayed spirited characters in relation to science with a focus on scientific research aimed at fighting infectious diseases.  The German character, Professor Max Gottlieb, is a bacteriologist and mentor to young Martin Arrowsmith who is much impressed by Gottlieb's dedication to pure research, and influenced by his quite unfair – for an educator – sarcastic despise for medical doctors.  Dedication to the mentor will push Arrowsmith to make scientific choices while confronting human sufferings.  It is because of his promise to Gottlieb that Martin Arrowsmith shall experiment on dying human beings without any doubt or even remorse, for the sake and integrity of science.  Indeed a control is needed as a standard for comparison therefore only half the patients must be treated.  As stated by Gottlieb- the scientist is intensely religious--he is so religious that he will not accept quarter-truths, because they are an insult to his faith.  "You must pity, oh, so much the generation after generation yet to come that you can refuse to let yourself indulge in pity for the men you will see dying. … Let nothing, neither beautiful pity nor fear of your own death, keep you from making this plague experiment complete" says Gottlieb.   Can experimentations on human beings be justified for answering the mere curiosity of a few scientists?  Is there an adequate justification for establishing the validity of a serum before its inoculation to dying human beings?  Here stands an open clash between the scientific method (need for control) and moral values.

Martin Arrowsmith is a captivating rebel combating the force of ignorance and greed to pursue scientific truth.  He is resisting pressure to become obedient, a new hero to scientific individualism.  He sees external pressures from institutions, like the powerful McGurk Institute of Biology, as a threat to pure science.  Indeed scientists need a great deal of freedom to pursue their educated curiosity besides fortitude in resisting pressure from institutions insuring their livelihood.  However his insistence in conducting 'his experiment' in the Caribbean where plague is spreading is quite astonishing.  After he sees the suffering from the plague he "had been tempted to forget experimentation".  In the Caribbean he finds opposition among the officials however he carries on with experimentation until he is himself confronted with the death of his wife Leora from the plague.

Illustration of the Black Death from the Toggenburg Bible (1411) most likely depicting the bubonic plague

Paul de Kruif, author of Microbe Hunters contributed significantly to the elaboration of Arrowsmith.¹  He and Lewis spent time together in the Caribbean establishing the material and characters for the novel.  No doubt Paul de Kruif influenced Lewis into thinking that medicine is not a science because of the lack of control experiments in medical research.  However Paul de Kruif formed an opinion on experimentation with human volunteers when he wrote in Microbe Hunters "But science is cruel, microbe hunting can be heartless, and that relentless devil that was the experimenter Walter Reed [the yellow fever hunter] kept asking: But is your experiment really sound?"  Was it in the interest of science and for humanity?  Yellow fever was at the time eradicated by Walter Reed and his team of brave soldiers which prompted Paul de Kruif to acknowledge the benefit of human experimentation with volunteers.

At present regulations and ethical guidelines for human experimentation exist.  They stress the voluntary consent of the human subject as being absolutely essential, and the experiment to be such as 'to yield fruitful results for the good of society'.

Footnote:
¹Lewis wrote to journalist H. L. Mencken "The book goes grand.  Paul de Kruif proves to have as much synthetic fictional imagination as he has scientific knowledge, and that's one hell of a lot.  It's going to be my best book—though it isn't just mine by a long shot."

Suggested Reading:

A free eBook of Arrowsmith (1925) at Project Gutenberg Australia

In 1930 Sinclair Lewis was awarded the Nobel Prize in literature 'for his vigorous and graphic art of description and his ability to create, with wit and humour, new types of characters' [Lewis Nobel Lecture at Nobelprize.org]

A 14-cent stamp in the Great Americans Series from Arago: People, Postage & the Post

Regulations and ethical guidelines for human experimentation, from the Office of Human Subjects Research at NIH, the National Institute of Health

'Loimographia: an account of the great plague of London in the year 1665' by London apothecary William Boghurst, 1666.  An online version of Loimographia is available at Open Collections Program, Harvard University Library.

A Journal of the Plague Year by Daniel Defoe, 1722 at Project Gutenberg

'Microbe Hunters' by Paul de Kruif, 1926 [Minst.org Library]

'An Introduction to the Study of Experimental Medecine' by Claude Bernard, translated by Henry Copley Greene, 1927.  The original French version was published in 1865.

'The Search' by C. P. Snow, 1934.  In 1958 the original version of the novel was cut quite considerably by the author who found it "more discursive than I can now bear."  [Excerpt from Part IV, Chapter 5: It was straightforward. Here was a published scientific communication; I knew it contained a mistake in fact; the motives behind it were irrelevant. In my hands I had the material to correct that mistake; unless I did so, and at once, I was an accessory after the fact.] [Note the reference to the Arrowsmith science, Part I, Chapter 5]

'The Plague' by Albert Camus, 1947.  In 1957 Albert Camus was awarded the Nobel Prize in literature, Excerpt from the Award Ceremony Speech: "In La Peste (The Plague), 1947, a symbolic novel of greater scope, the main characters are Doctor Rieux and his assistant, who heroically combat the plague that has descended on a North African town.  In its calm and exact objectivity, this convincingly realistic narrative reflects experiences of life during the Resistance, and Camus extols the revolt which the conquering evil arouses in the heart of the intensely resigned and disillusioned man."

Bubonic Plague, Rats and Uncle Sam in 1941
Combatting the Rat Menace, Popular Mechanics Magazine, March 1941, Vol. 75, No. 3 [Search Google Books]
Note: In Arrowsmith rat-extermination takes a comical turn