Anti-Vaxxers and Water Witches: Mistrust of Science and the Limits of Reason

How can you reason with someone who is determined to believe misinformation? One doctor shares his reflections.

“Come now, and let us reason together.” –Isaiah 1:18

"Reason is, and ought only to be, the slave of the passion." –David Hume1

A few weeks ago, having been fully vaccinated against COVID-19, I ventured out for a long-postponed haircut without wearing a mask, knowing that the pleasant but tempestuous woman who regularly cuts my hair had received the single-shot Johnson & Johnson vaccine. But when I told her I had received 2 doses of the Pfizer vaccine, she looked horrified. “Oh, no!” she said, “That vaccine is going to rewrite your DNA and leave your immune system damaged for life!” I decided this was not the time to challenge her or to explain that, no, the m-RNA vaccines do not rewrite one’s genetic code or destroy the immune system—especially with her scissors 3 inches from my face.

Then, a few days ago, I read about the increasing use of so-called water witches in California, which is experiencing extreme drought conditions. According to the New York Times, these “water dowsers” claim that they can “…locate streams of water in the fractures in the earth’s bedrock, using 2 L-shaped rods that together resemble an old-fashioned television antenna.”2 These individuals are now heavily booked and well-paid for their services, despite the fact that hydrogeologists describe water dowsing as “totally without scientific merit.”2

The common thread in these personal vignettes is, of course, a deep-seated denial of science and a mistrust of scientific experts—a word that is nowadays pronounced with a kind of dismissive hiss. Indeed, experts in epidemiology and infectious disease, such as Anthony Fauci, MD, are not merely doubted by a substantial proportion of the public—they are threatened with bodily harm for advocating vaccination against COVID-19.3

It is easy to explain away such science denial as the result of mistaken information and biased reasoning, exacerbated by grossly misleading claims on social media.4 To be sure, these factors do contribute to science denial and the derogation of scientific authority. As physicians, we have an obligation to provide our patients with accurate information that might counteract such irrational and unfounded beliefs.5

But as psychiatrists, we know that reason has its limitations, absent a deep understanding of the feelings—indeed, the passions—that shape human belief and behavior. The great Scottish philosopher, David Hume (1711-1776) understood this well, arguing, in his Treatise of Human Nature, that “…reason is, and ought only to be, the slave of the passions.”1 According to philosopher AT Nuyen, Hume was not negating the importance of reason in shaping human belief and behavior, but merely putting it in proper perspective—arguing, in effect, that “…reason alone does not move one to act. The force that propels one to action is the passion, whether it be love, or anger, or pride, or envy, or fear, or desire.”1

Hume’s great insight has been amply confirmed by modern-day psychological research, notably that of Robert Sapolsky, PhD, a professor of neurology and neurosurgery at Stanford University.6 Sapolsky’s studies of cognitive function have convinced him that, “You can’t reason somebody out of something they weren’t reasoned into in the first place,” and that “…We’re certainly set up to only have resonating in our head the stuff we want to hear.” He adds that, “…people who are least curious, most unwilling to explore novelty, [and] most reflexively hostile about it are people who are anxious.”6

And who better to empathize with and explore anxiety than psychiatrists? Indeed, Sapolsky urges us to emulate the teenager, whose “…deeply felt sense of empathy” is often lacking in adults. Had I been doing therapy with someone like the woman who cuts my hair, I would have homed in on the anxiety that probably underlay her unfounded beliefs about COVID vaccines. If I were working therapeutically with the rancher or vineyard owner shelling out good money to a “water witch,” I might focus on the understandable feelings of despair and desperation driving that behavior. Yes, I would also gently guide these individuals to sources of accurate information—but only after connecting with them on an emotive level. As another philosopher, Blaise Pascal (1623-1662) wisely put it, “The heart has its reasons which reason knows nothing of... We know the truth not only by the reason, but by the heart.”7

Dr Pies is professor emeritus of psychiatry and lecturer on bioethics and humanities, SUNY Upstate Medical University; clinical professor of psychiatry, Tufts University School of Medicine; and Editor in Chief emeritus of Psychiatric TimesTM(2007-2010). He is the author, most recently, of The Levtov Trilogy; and Just Take it One Miserable Day at a Time.


1. Nuyen AT. David Hume on reason, passions and morals. Hume Studies. 1984;10(1) 1984:26-45.

2. Albeck-Ripka L. Two rods and a ‘sixth sense’: in drought, water witches are swamped. New York Times. July 17, 2021. Accessed July 21, 2021.

3. Mello MM, Greene JA, Sharfstein JM. Attacks on public health officials during COVID-19. JAMA. 2020;324(8):741-742.

4. Ortutay B, Seitz A. Defying rules, anti-vaccine accounts thrive on social media. AP News. March 12, 2021. Accessed July 21, 2021.

5. Pies RW, Pierre JM. Believing in conspiracy theories is not delusional. Medscape. February 4, 2021. Accessed July 21, 2021.

6. Robert Sapolsky on how to become ‘less twitchy,’ embrace empathy. FRED Leadership. Accessed July 21, 2021.

7. Pascal B. Accessed July 21, 2021.

For Further Reading

Brumfiel G. Anti-vaccine activists use a federal database to spread fear about COVID vaccines. June 14, 2021. Accessed July 21, 2021.