I liked this book, a succinct refutal of a bunch of tropes associated with innovation, littered with nice analogies and good quotes, and mercifully short.

At any point, innovation can only occur at the edge of possibility, at the adjacent possible. If you’re not bold enough, it’s already been done. Too bold and you’re ahead of your time. This model nicely explains why important discoveries are often arrived at simultaneously by multiple discovers in different places (called multiples).

Johnson describes environments conducive to innovation as liquid networks. In a gas, atoms are far apart and chaotic. They may collide, but they won’t stick. In a solid, atoms are too constrained and won’t have a chance to interact at all. A prehistoric human society is like a gas: ideas may form but the lifestyle is too chaotic for anything to stick. Religious autocracies of the European Dark Ages and post-Enlightenment Arab world are like a solid: society is too restrictive to even let ideas form in the first place.

In general, Johnson rejects the narrative of the Eureka moment, attributing success to slow hunches, which take a long time to brew in a person’s mind. In a liquid network, multiple slow hunches have a good chance of meeting, and an insightful person can combine the two into a coherent idea.

The author compares the web to cities and coral reefs, both as examples of productive, dense, liquid networks where entities flow freely. Citing Scale by Geoff West, he notes that big cities aren’t just proportionally more inventive than small ones, but super-linearly so, with higher per-capita output. Just like cities allow free mingling of people and their ideas, the web enables this for the whole world serving like a “dating service for promising hunches”, increasing serendipity.

The way to nurture a slow hunch is to take copious amounts of notes, as evidenced by Commonplace books (new to me), which became popular during the European Renaissance, popularized by Locke. Charles Darwin’s commonplace book is mentioned quite a bit as an example.

The “missed connection” example he provides in a non-liquid network are two hunches that could have met to stop the 9/11 aircraft hijackings, but never did due to the solid-like FBI bureaucracy.

1. The Phoenix Memo advising about bin Laden’s coordinated effort to send students to US aviation schools.
2. Moussaoui’s arrest at a flight training school in Minnesota.

Continuing the analogy of liquid networks and water, Johnson lauds desirable spillover from one group of humans to another, encouraging cross-pollination of ideas, and a multidisciplinary approach. Examples of this include Building 20 at MIT, the “womb of the institute”, a temporary building that was at the heart of hacker culture, discoveries like LIGO, and great companies like Bose. By having a place that breeds so much intellectual diversity, you can imagine ideas crossing boundaries. When one idea goes from one domain to another, it’s called exaptation. For example, Gutenberg’s printing press borrowed the screw press mechanism, which was used for pressing olives into oil and grapes into wine.

Naturally, as ideas form and evolve, many leads go nowhere. Edison said “I didn't fail 1,000 times. The light bulb was an invention with 1,000 steps.” At this point, this is definitely a cliche.

The book concludes with a series of 2x2 tables showing four kinds of inventions (borrowed from Wealth of Networks):

+------------+------------+---------+
|            | Individual | Network |
+------------+------------+---------+
| Market     | 1          | 2       |
+------------+------------+---------+
| Non-market | 3          | 4       |
+------------+------------+---------+

1. Market / individual: solo entrepreneur or private corporation.
2. Market / network: marketplace with multiple individuals.
3. Non-market / individual: hobby or amateur scientist, sharing ideas freely.
4. Non-market / network: open source or academic env where ideas can be built on freely.

Quadrant 1 occupies the popular imagination: instigated by solo inventor driven by profit like Edison, or in this case he picks on Carrier, inventor of the modern air conditioner. But in an analysis of inventions from 15th century until the present, Johnson concludes that most inventions fall into quadrant 4, the non-market network.

The author doesn’t do a convincing job of explaining why each invention falls into each quadrant, and in many cases I think the call is very subjective, but the framework is interesting nonetheless.

Johnson ends in an interesting take on Darwin’s work. Darwin’s big idea is often popularized as survival of the fittest, but Darwin himself makes clear that the right environment is perhaps even more important. In The Structure and Distribution of Coral Reefs, published in 1842, Darwin described how coral reefs were found in some tropical areas but not others, with no obvious cause. Tropical waters contain few nutrients yet a coral reef can flourish like an "oasis in the desert”, supporting over one-quarter of all marine species. His seminal work concludes with this passage:

It is interesting to contemplate a tangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with reproduction; Inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone circling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.

References some books that have been on my radar, but might be worth delving into:

• The Act of Creation by Arthur Koestler
• How Buildings Learn by Stewart Brand (and TV mini-series)
• The Structure of Scientific Revolutions by Thomas Kuhn