Scale: The Universal Laws of Growth, Innovation, Sustainability, and the Pace of Life in Organisms, Cities, Economies, and Companies
Author: Geoffrey West
From the Amazon description of this book: “[West] has found an underlying simplicity that unites the seemingly complex and diverse phenomena of living systems, including our bodies, our cities and our businesses.”
The topic intrigued me. Was there really a common thread that tied all of this stuff together? The author made and reinforced the point that scale is a useful predictor for many features of things (animals, cities, companies, etc.). “If you know the size of a mammal, you can use scaling laws to learn everything from how much food it eats per day, what its heart-rate is, how long it will take to mature, its lifespan, and so on.”
What I liked about this book:
- It forced me to think more clearly about the underlying relationship between mass and surface area. As an object gets bigger without changing its shape, the mass increases as a cube³ while the surface area increases as a square². The result is that without some accommodation of shape it will eventually reach a point where it can’t support itself.
- The author highlighted examples where we tend to apply linear thinking to non-linear environments. For example, human weightlifter strength has a 2/3 scale factor – strength increases by two orders of magnitude for every 3 orders of magnitude increase in body weight. He concludes that the strongest man in the world (in the 1956 Olympics) was the middle-weight who outperformed his predicted capacity rather than the heavy-weight who lifted the most weight and under-performed his predicted capacity. Debatable, but fun.
- Another example I found interesting was scale as applied to the dosage of medicine. The author makes the point that many dosage instructions are determined on a linear scale with weight, while they should, in fact, be calculated differently. A 30lb child and a 150lb adult should not merit a 5x difference in dosage. The same concept holds true for scaling up recipes in the kitchen. If you scale linearly from home cooking to commercial kitchen, you’re gonna have a bad time.
- The changing lengths of coastlines due to fractal dimensions was a new concept for me. The point here is that if you measure the coastline of a nation (in Kilometers, for instance), the number you come up with is going to vary based on the scale that you use to measure. An example from Wikipedia:
- Power law scaling applies to many aspects of cities too. For example, the number of gas stations in a city scales sub-linearly with population at a factor of 0.85. So for every doubling in the population of a city, you can expect only an 85% increase in the number of gas stations. This is an example of the phenomenon that drives efficiency in cities. The flip side is that when applied to metrics like crime rates, cities tend to show a super-linear scale effect, meaning that crime increases faster than population growth. C’est la vie, I guess :).
What I didn’t like about this book:
- There are a number of fair criticisms about the author’s conclusions and the strength with which he makes them. Suffice it to say that many of the points the author makes are subject to debate.
- As an audiobook, its hard to grasp everything because of the many charts the author references. More importantly, because I didn’t see the charts in real-time as I was hearing the message, it was harder for me to call BS when things didn’t make sense.
- The author is a very accomplished physicist and academic, and his writing style and language won’t let you forget it. Over and over again I found myself shaking my head at his use of big words when small words would do.
- The application of scale as a ‘science of companies’ didn’t resonate with me. It felt like a vast oversimplification without any real utility.
The book is entertaining and its many anecdotes and analysis are worth a read if this sort of stuff interests you. The only thing that might be better is if someone compiled the most interesting of them into a list of short articles or blog posts.