Why do we die? Why does any animal die? How old can we expect an average individual of any species to become, and what does that have to do with its body size or heart rate? In “Scale”, Geoffrey West outlines a simple mathematical model that answers all of the questions above with amazing predictive power.

West then applies the same model to answer similar questions about cities. Do they grow forever? How is the number of gas stations related to the crime rate and resource requirements? Again, the theory that West and his colleagues have developed makes impressively accurate predictions. Less accurate than with the biological questions, but in a sense it even predicts that it should be less accurate for cities!

This is one of those books I could not put down. I recommend you read this book, too, if:

  • You are sensitive to the sensations of beauty and awe that some mathematical theories convey, or
  • you want to see an aspect of biology that is as “hard” a science as physics is, or
  • you think about studying economics (or biology or city planning), or
  • you just want to learn something new that’s interesting.

The final application West writes about I find quite worrying: economics. West’s theory predicts that to sustain itself, the (global) economy needs to grow faster than exponential, leading to a singularity after a finite amount of time. Fortunately, this part is less well explained – perhaps because it is a new and active area of research; but if any of you is an expert on this, please let me know!