In the forward he writes (emphasis mine):
I have thought about this project for some time. I have often wondered what little tidbits of information I should give you. I started to slowly post these 140-character granules of wisdom to Twitter; Twitter acting as a kind of repository of ideas. After several months of accumulation, I started to come up with a plan where the granules would have a bit of longevity.
When I found out I had rheumatoid arthritis and upon turning forty, I knew I wanted some of the ideas I have communicated over the years to stick within your brain.
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