Substack & information density

If high information density is your goal, text is best. Substack may be the best aggregator of high information density text.

I’m in the middle of reading a book with the ponderous title The Master Algorithm: How the Quest for the Ultimate Learning Machine Will Remake Our World. The book is pretty good, and I’m about 2/3rds of the way through it. I can’t help but wonder, though, whether Arnold Kling is correct, when he writes of non-fiction books:

I speculate that nonfiction books are headed down the path of academic journals. They will be useful for academics positioning themselves for tenure, but they will be too slow and ponderous for communicating ideas. People who really care about ideas will turn to reading and writing substacks instead of books and journals.

In a world awash in information, formats which deliver high information density seem to hold more promise than those which are not information dense¹. I frequently lament that podcasts have terrible information density. I call them low-bandwith, but low information density is another way to think of it. Consider Andrew Huberman. His podcasts are multiple hours long:

And this particular 2-hour podcast is the first in what promises to be a 6-part series. Assuming that each part in this series is approximately the same length, that’s an 8-hour podcast!

I can’t find a transcript for this podcast, but here’s a transcript for another one of his podcasts, on supplements and health. It’s a 50 page, single-spaced PDF. Surely you can intuit how scanning through a 50 page PDF to extract salience and meaning is higher-bandwidth than listening to two people drone on for more than two hours. A reasonably intelligent person can scan through a 50-page document in 20 or 30 minutes, focus on those areas of interest, and ignore the rest.

In any event, to go back to the original point in this piece, Arnold Kling’s claim is that Substack posts are information-dense, whereas non-fiction books, Twitter, and podcasts are not. I think this is true, contingent on curating your Substack reading. You need to select for high-quality writers who convey information succinctly. (There are various popular Substack writers, who I’ll not name, who are in desperate need of an editor to foist concision upon them.)

I frequently hear the claim that podcasts (or audiobooks) allow you to consume valuable information while, say, washing the dishes or driving. And, while that is superficially true, I have to wonder how effective this strategy is. I think people are overly optimistic about their ability to multitask. If you were to test the recall of someone sedulously listening to Andrew Huberman’s podcast while doing the dishes, or driving, or lifting weights, or walking the dog, I suspect you’ll find that the person didn’t actually understand much of what was said. His podcasts are complex! And they’re lengthy. They are the aural equivalent of long tomes. The notion that you can understand what Andrew and his guests are talking about, while engaged in another activity, strikes me as fanciful.

Given all of this, I have to wonder: why not avail yourself of a platform that is information dense? Just because you can multitask does not mean that doing so is effective.

1. Out of curiosity, I asked ChatGPT to write an outline for this post. Its outline follows. You’ll notice that (1) the outline is fairly good, and (2) that this post largely ignores it. While the outline is good, I think the point can be made more succinctly.

• Introduction

  • Explanation of the concept of information density

  • Overview of the rise of Substack newsletters and podcasts as popular mediums for information consumption.

• Information Density in Substack Newsletters

  • Explanation of how Substack newsletters are designed for information-dense reading

  • Discussion of the pros and cons of information density in newsletters (e.g. ability to quickly consume and retain information vs potential for information overload)

  • Examples of Substack newsletters known for their high information density

• Information Density in Podcasts

  • Explanation of how podcasts are designed for a more relaxed and leisurely consumption of information

  • Discussion of the pros and cons of information density in podcasts (e.g., ability to deepend understanding of a topic through extended discussion vs potential for listeners to tune out or lose focus)

  • Examples of podcasts known for their high information density

• Comparison of Information Density in Substack Newsleters and Podcasts

  • Comparison of the different ways in which Substack newsletters and podcasts convey information

  • Discussion of the unique advantages and disadvantages of each medium in terms of information density

  • Analysis of which medium may be better suited for different types of information or audiences

• Conclusion

  • Summary of the main points discussed in the blog post

  • Personal recommendations for how to effectively consume information through Substack newsletters and podcasts

  • Call-to-action for readers to share their own thoughts and expereinces with information density in these mediums