The Weight Test
Here's a different approach. Don't ask what you can doubt. Ask what you've tested.
Not intellectually. Physically. Metabolically. With hours and failure and adjustment.
You think you know how to build muscle. Have you gained twenty pounds of it? You think you understand sleep architecture. Have you optimized your own? You think you grasp persuasion. Have you changed anyone's mind about something that mattered?
The body is an epistemological filter. It will not pretend. Feed it the wrong macros and it softens. Train it incorrectly and it breaks. Deprive it of sleep and watch your "clear thinking" dissolve into fog.
This is not anti-intellectual. This is pre-intellectual. Before you theorize about human nature, optimize one human—yourself. Before you write about discipline, demonstrate it where it costs something. Before you speak about transformation, transform.