Reisman, Jonathan
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Reisman frames the human body through the lens of "millions of years of sex and death" — reproduction and mortality as the two evolutionary forces that shaped it — and argues most body parts represent good design given the constraints, with the throat as a notable exception: because the esophagus (food) and trachea (air) pathways sit millimeters apart and cross at the same junction, choking is an ever-present risk, compensated for only by mechanisms like the gag reflex, cough, and a "mucus elevator" that clears debris from the lungs. He walks through the body's development as a simple tube that folds from an embryonic disc and later sprouts specialized openings and organs at each end, and discusses the hand (and especially the thumb, whose loss surgeons will go to greater lengths to prevent than other fingers) as an example of unusually elegant design, crediting its tendon-based "puppet string" architecture for its dexterity.
He discusses several underappreciated organs: the kidneys (among the body's most energy-hungry organs, continuously fine-tuning blood chemistry) and the liver (which he compares to "15 organs in one" — detoxifying, packaging cholesterol, producing clotting factors, regenerating itself when partially removed, unlike most organs). He contrasts the heart's actual function (a simple mechanical pump moving blood under pressure to reach every cell) with its outsized cultural and poetic association with love and passion, calling it "the biggest disconnect between how organs are talked about in poetry... versus actual function." On reproduction, he describes menstruation as an unusually slow bodily rhythm (taking over a decade to begin, cycling only monthly) whose cessation, unlike other bodily rhythm failures, is not a medical emergency but the intended outcome of pregnancy, and discusses the genitals as the body's only organs not required for moment-to-moment survival — sometimes actively working against self-preservation by driving risky behavior. Speculating on "improving" human anatomy, he suggests testicles could ideally function at core body temperature (removing the need for them to hang exposed) and that protecting the uterus/fetus from trauma or STDs during pregnancy remains a real design weakness, noting early-stage research into artificial wombs (which have already extended fetal gestation in animal studies) as a potentially transformative technology for premature infants.
On feces, he describes diarrhea as an evolutionarily "brilliant" mechanism by which gut pathogens increase their own transmission via the fecal-oral route, and reflects on how discussing bodily functions with strangers in clinical settings, though socially taboo elsewhere, gives doctors an unusually direct, therapist-like window into patients' psychology, fears, and mortality anxieties. He discusses the emergency room as a uniquely revealing vantage point on the "human condition" — citing Chekhov's observation (Chekhov himself a doctor) that people of all social classes "have the same ugly bodies" — while noting that repeated exposure can make doctors go numb to it, a numbing he says he actively resists through a writer's habit of continually re-noticing what he sees.
Discussing his career practicing medicine in remote regions (Arctic Alaska, Kamchatka and Chukotka in Russia, Nepal, Antarctica, India, Native American reservations, Appalachia), Reisman describes formative experiences with Arctic Indigenous diets (largely raw marine-mammal fat, eaten for lack of fuel for cooking) and describes being informally "adopted" by elderly Russian and Koryak women whose insight and education (a legacy, he notes, of the Soviet education system's emphasis on literature and science) left a deep impression on him. Asked about the war in Ukraine, he calls it tragic and "seemingly pointless," reflecting personally on what he sees as Russia and Ukraine's historically unrealized scientific and medical potential and expressing hope that scientific collaboration could eventually transcend political conflict — framed explicitly as his own regretful, non-expert reflection rather than geopolitical analysis. He also discusses Paul Farmer (founder of Partners in Health) as a formative influence on his own commitment to global health work, citing cheap, high-impact interventions (oral rehydration therapy, amoxicillin) that remain unevenly available worldwide.
On the limits and humility of medicine, Reisman argues that a large share of historical medical practice — from bloodletting to many still-common procedures — has later been shown to be ineffective or harmful once subjected to rigorous testing (citing sham-surgery studies on knee arthroscopy and cardiac stenting for stable angina that failed to outperform placebo controls), and predicts "every doctor today will look like a total quack" to future generations. He argues modern medicine is severely data-starved relative to what's needed for precision care (a doctor typically works from a few minutes of conversation and limited symptom data rather than rich longitudinal data), and expresses hope that AI-assisted analysis of much richer patient data could eventually transform diagnosis and treatment — while also expressing skepticism that any given medical intervention's real net effect on broad population outcomes is well understood at all. He also reflects, drawing on his math undergraduate background, that the abstraction of mathematics and the messy resilience of biology are more connected than they initially seem (citing fluid dynamics and symmetry as places math directly illuminates the body), while cautioning that computational models of biology risk oversimplifying a system whose redundancy and adaptability may be difficult to replicate in engineered systems like robots or brain-computer interfaces.
The conversation closes on mortality and meaning: Reisman discusses his own decision, made on his first day of medical school cadaver dissection, to donate his body for the same purpose; reflects that "no one knows what they're doing" and that suicide's prevalence was one of the most shocking realizations of his adult life, encouraging listeners struggling with hopelessness to "keep up the good fight"; and states that, as a medical student, he found that what troubled him most about death was not the moment of dying itself (which he suspects is often less painful than commonly feared) but the grief left behind in those who loved the person. Asked for the meaning of life, he suggests that "why" questions may be an evolutionary adaptation — originally practical (why does this plant make me sick, where do the deer go) — that humans have extrapolated into unanswerable existential questions, speculating that this endless human drive to ask "why" may itself be a tool by which the universe comes to understand itself.
Excerpts
On why the throat is, in his view, the body's worst-designed structure:
“We have two tubes that are right next to each other in the throat... you slip up once — you laugh while eating, or you speak while trying to swallow — and you die from choking. It seems less than optimal... it seemed set up almost for failure, and we developed all these mechanisms as a compensation: the gag reflex, the cough, even something called the mucus elevator.”
On why he considers the heart the biggest gap between cultural symbolism and actual biological function:
“The heart... it's just a simple mechanical pump — that's all it is. I don't want to downplay it, it's amazing, but it just fills with blood and squeezes, fills and squeezes, and that squeezing creates the blood pressure you need to get blood to every cell in your body... we ascribe all these things like love and passion and life itself to the heart, but it's the biggest disconnect.”
On what sham-surgery and placebo-controlled studies have taught him about medical certainty:
“It made perfect sense in my head, knowing the biology, the biochemistry, the anatomy — it must work. I gave it to the patient, they got better, and that's happened 20 times in the last year. But when you actually do the study, it doesn't help — maybe it hurts... those placebo-controlled studies are essential, because it is shocking how hard it is to figure out what the hell's going on with our bodies.”