#154 - Steve Levitt, Ph.D.: Climate change, mental health, the ethics of experiments, and more

Levitt's dream is that every newspaper article has a sidebar with its 5 core factual claims, separately verifiable. In scientific discourse, this manifests as his sharp distinction between the role of data (establish the facts) and the role of theory (interpret the implications). He criticizes economists who blend these roles — building models that embed both the facts and their interpretation, making it impossible to know which assumptions are doing the work.

Levitt frames this as one of the best 'liberation' decisions he has ever made — analogous structurally to his decision not to care what other people think. Both are decisions to stop spending cognitive resources on a class of problems. He explicitly connects the practice to the idea of radical acceptance: these are imperfections he simply accepts rather than optimizing. Attia notes the same principle applies to cognitive load in clinical practice — decision fatigue is real and finite, and protecting it by pre-deciding trivial choices is standard among high-performance practitioners.

Levitt describes coming to radical acceptance of his infant son Andrew's death from meningitis — not through therapy or deliberate work, but as a near-automatic response. He credits the experience with restructuring his parenting toward extreme autonomy and acceptance of his children as independent people. He connects the practice to DBT's concept of radical acceptance, which Attia has studied. Levitt's practical test: was the thing beyond his control? If yes, accepting it as real costs nothing and spending energy on it costs something. Notably, he finds radical acceptance easier for large catastrophic events (obviously beyond control) than for small daily frustrations (where the illusion of control persists).

Levitt describes this analysis — done by an economist he cannot name, roughly 10+ years ago — as a genuine intellectual shock that changed his thinking on climate change. He had been discounting the future cost of climate change (as economists are trained to do) and treating it as a budget problem. The utility-function analysis revealed it is actually an asymmetric-risk problem: even small probabilities of civilizational-scale harm demand investment shares that are much larger than the probability suggests. He calls this the strongest case for serious climate R&D even among people who doubt the models.

The intellectual origin is Sam Harris's Waking Up, specifically the observation that the right brain hemisphere — which is non-verbal — is effectively dominated by the speaking left hemisphere. Levitt's hypothesis: we are in a relationship with only half our brain. The non-verbal half has access to a fundamentally different quality of experience. His practice is not trying to silence the left hemisphere but to create conditions where the right hemisphere can participate: experiencing a potato peel as texture and resistance rather than 'potato,' experiencing a sunset as color and light rather than 'sunset.'

Levitt applied this sequentially at MIT: tried macroeconomics (abandoned quickly when he could not develop intuition), tried theory (abandoned a little later after writing a couple of papers), then arrived at empirical data analysis — which he had been doing recreationally as a child (manually computing baseball correlations on a scientific calculator at age 9). In retrospect, the empirical path was obvious from his revealed preferences. The failure to see it earlier was driven by status-chasing. The general principle: your revealed preferences in leisure time are a better signal of natural aptitude than your stated career aspirations.

The stratospheric sulfur approach mimics major volcanic eruptions like Mount Pinatubo. Cost estimate: a few hundred million dollars per year. The cloud-seeding approach uses 10,000 solar-powered GPS dinghies spraying ocean salt upward to seed reflective clouds over dark ocean surfaces — simulations suggested it could offset all of global warming. Levitt's analogy: the goal is to keep babies' poop off the floor (a diaper solves that); you don't have to eliminate poop. The strategic framing: objectives, strategies, and tactics must stay distinct. Reducing carbon is a tactic. Cooling the planet is the objective. Conflating them locks debate into the most expensive possible solution.

Levitt's dream journalism format: every news article would have a sidebar listing the 5 core facts on which the piece is based — separately checkable, separately verifiable. In debate format: each participant lists 10 facts they believe true before speaking. If they agree on all 10, the debate is about implications. If they disagree on facts, you have a different kind of problem entirely. The same bifurcation explains why macroeconomics makes so little progress: the models are so complex that it's almost impossible to agree on what the facts even are, let alone what they imply.

Attia adds that the first real dent in tobacco came not from information but from a law requiring anti-tobacco ads to run alongside tobacco ads — the anti-tobacco ads were so effective that tobacco companies voluntarily pulled all advertising rather than subsidize their opponent. The reduction was driven by changed defaults and social norms (now smoking marks you as 'crazy'), not knowledge. Levitt's challenge: name one major human problem driven by externalities that was solved by asking people to behave better. He does not believe one exists.

Attia agrees on the asymmetry but is more pessimistic about implementation: even with consensus on solutions (e.g. next-generation nuclear, which 'anyone who has studied energy seriously' believes is necessary), political palatability is a separate bottleneck. Levitt acknowledges this but argues the insurance value justifies the investment regardless — you want to know whether you have an exit before you're in crisis. The comparison is to Moncef Slaoui's pre-pandemic proposal to pre-develop vaccines for all known pathogen classes: rejected at the time as wasteful, would have been 'literally the best investment of all time.'

Levitt's organ-donation argument: a healthy live kidney is worth hundreds of thousands of dollars in averted dialysis and suffering. If you paid donors $100,000 you might get 50 million volunteers. Wall Street bankers would sign up. In that world, the 'exploitation of the vulnerable' framing collapses because you have surplus volunteers across income levels. The IRB objection to paying is circular: it assumes small payments, where the objection is valid. It does not engage the high-payment world where the objection vanishes. Attia endorses the logic: low payments disproportionately target vulnerable people, which is the very harm IRBs claim to prevent.

Levitt distinguishes his practice from standard meditation: he is not trying to quiet his brain but to observe with all senses free of language. Most things we do — peeling a potato, listening, walking — can be done without the internal word stream. The finding: negative emotions like anger and victimhood seem to require a narrative (language) to sustain themselves. In the absence of naming, the emotional valence flattens. Attia notes this could likely be augmented by psychedelic compounds. Levitt practices this for ~5 minutes at bedtime.