Overview
If you know 1,000 things, but get smarter at a rate of 5% per week, how long will it take to become smarter than sombody who knows 10,000 things?
There are lots of fun ways to approach this practical problem, but we're going to use the rule of 72 by first figuring our how long it takes to double our knoweldge, then counting how many times we need to double 1,000 to reach 10,000.
If we divide 72 by our growth rate of 5%,
we learn it takes approximately 15 weeks to double our knowledge. We need to 10x our knowledge, so
In 3.5 doublings we'll match the expert's knowledge and know 10,000 things - in just 52 weeks or one year we are ten times smarter.
Extrapolating, in 80 weeks (less than two years), we'll know 50,000 things, thus is the magic of compounding.
Two lessons here:
- Train your juniors and filter by growth rate (motivation etc) over base intelligence.
- Mental models like the rule of 72 help you solve all sorts of things when practised regularly.
In reality we'd need to consume more and more each week to keep that 5% constant, but for an approximate mental model it's acceptable.
How to finish a book a week and systematically grow your brain.
We maximise three variables:
- Consistency
- Retention
- Speed
Consistency
You can't grow by 5% if you stop reading, and nothing stops you reading like an uninteresting book. The solution therefore, is not to read things you're not interested in (your interests will expand the more you read, so there's little risk of echo chambers).
Two things that help me remain consistent:
- I prioritise reading and set a goal of reading at least 50 pages per day before 8pm (I get up early and read for an hour). Reading in bed is a bonus!
- I don't finish chapters I'm not interested in, nor books. I do all I can to avoid the wall that stops me picking up a book and making progress; the knowledge opportunity cost towards the compounding model is too high.
Retention
Regularly revisit what you've read, either through practice or flashcards. Practice is useful but limited, and you can't practise everything. Flashcards are comprehensive but manual. I built an app around what works for me, and I'd encourage readers to do the same! Your memory works in amazing ways, the better you know something the less you need to revisit it - this is called Spaced Repetition and established tools like Anki are built around it. I made my app fun to use, and I use it for 5-15 minutes every day to keep my knowledge fresh.
Speed
This is the least important, but I've tried everything. Here's what worked for me and what didn't.
| Method | Findings |
|---|---|
Speed/Skim Reading | This cost me time in the long run. We've seen the compounding model, we don't need get-rich-quick schemes. |
Using a stylus | Game changer. I read with a pen and drag it quickly over words to guide my eyes. You can build up to faster movements as you read more. |
Stopping subvocalising | If you say the words aloud in your head as you read them, you can only read as fast as you can speak. I cut this out by saying "1, 2, 3, 4" in a loop as I move the stylus. I find it marginally speeds up my reading but I enjoy reading more when I subvocalise. |