Frailty index and bidirectional causality

On this, our 316th Evolutionary Lens livestream, we discuss health, science, and the Cartesian crisis as it relates to global events. First: a new paper finds that infection tends to lead to greater frailty in older people. This reverses the causality of Terrain Theory of Disease (frailty of the body leads to greater susceptibility of infection), and also provides support for a prediction made by Bret and his co-author Debbie Ciszek in the unpublished, longer version of their reserve capacity paper from 2002. Then: what we are seeing on our personal media feeds does not make us eye-witnesses to anything—not necessarily. Plato’s Cave of Mirrors means that we are all fed different media diets, and skills such as observation, discernment, and hypothesis generation, inherently fail when nobody can establish what is actually true. Recommendation: start comparing notes with other people as to what they are seeing, rather than what they think it means.

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Mentioned in this episode:

Ragusa et al 2026: https://academic.oup.com/biomedgerontology/advance-article-abstract/doi/10.1093/gerona/glag043/8497853

Gavazzi & Krause 2002: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(02)00437-1/fulltext

New York Magazine article on Casey Means: https://nymag.com/intelligencer/article/casey-means-and-the-myth-of-the-root-cause.html

Weinstein & Ciszek 2002: https://pubmed.ncbi.nlm.nih.gov/11909679/

Journalist Mizrahi on X (maybe): https://x.com/eliseevanews/status/2029700361297051829

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