Dear Hank & John 444: Hank Brown
Mar 18, 2026
They unpack why humans are not optically transparent and what light reveals about our bodies. They imagine whether life on a moon could realize it orbits a planet. They speculate about prehistoric dreams and the rise of language and art. They explain how Good.Store partners work and talk through coping with parental memory loss and anticipatory grief.
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Why People Aren't Transparent
- Human tissues vary in transparency because of how visible light interacts with molecules and structures.
- John and Hank note x-rays pass through some tissues while visible light is scattered or absorbed, so we aren't see-through under normal light.
How Moon People Would Discover Their Planet
- Surface-dwelling moon inhabitants could deduce orbital relationships with a few centuries of shared science and record-keeping.
- Hank argues subsurface life like Europa's ocean would likely never know about their planet because thick ice blocks external observation.
Surface Perspective Makes Cosmic Facts Easier
- Being on a planet's surface makes discovering wider cosmic structure easier than for subsurface life.
- Hank compares Europa's subsurface organisms to humans blind to aspects of our own reality, highlighting limits of knowledge bound by environment.
