It’s been awhile since last I blogged here. I recently finished listening to S. Page’s Great Courses Complexity which reminded me of a couple of books I read last year by N. Taleb (Antifragile, Black Swan, etc.) which inspired me to start philosophizing again about the long term future of humanity. As I started thinking more about what it was I wanted to explore with this post, I came quickly to realize that I was down a rabbit hole, and speaking of rabbits…

The Tale of the $500 Free Rabbits

At the beginning of COVID, my wife, worried that the kids would not be getting to play with friends for awhile, asked if I would be ok getting rabbits again. I immediately recognized this as a trap. Last time I said yes to rabbits, they instantly became my responsibility. Just like with the kids.

Hence, I wisely said “No way.” I was outvoted. A few days later, wife sent me to pick up free rabbit #1. A few days after that, she brought home free rabbit #2, a young male. A week after that, rabbit #1 developed a limp resulting in a $100 vet visit where we confirmed it was a doe (female). 30 seconds later we had a litter of baby rabbits.

Ok, that’s an exaggeration, it didn’t happen until fall, but we ended up with 5 rabbits in the house. All. Winter. We managed to get rabbit #2 neutered before a second incident. However, one of the new bunnies was also born with outside genitals, so it wasn’t long before we were up to 15 rabbits. This situation was not a surprise to me, and I urged my wife at every juncture to find a new home for boy bunny. Eventually she did, but not until after another litter of 5. To her credit, she found new homes for 13 of the bunnies, and neighborhood cats took care of the rest.

I learned why it is called animal "husbandry". My involvement reluctance was deemed irrelevant. Over this last summer, I converted the kids playhouse into a rabbit enclosure. Also over the summer I experienced the supreme satisfaction of removing botfly larvae from rabbits, but not until after another diagnostic vet visit costing $400. In December, rabbit #1 burrowed out of my fine enclosure and was taken by a fox (according to surveillance system). We are now at 3 rabbits. Rabbits running around the yard is incidentally why gardening efforts the last two years have been minimal.

Resilience

Our rabbit colony continues to exist because mama rabbit sacrificed herself by bolting, forcing the fox to chase her instead of going into the enclosure and killing all the rabbits as foxes often do with prey in captivity. Whether this altruistic final act was intentional or instinctual, it demonstrates the difference between individual and collective success. If our primary goal was to maintain colony size (instead of letting children learn responsibility and empathy), I could have kept the rabbits in separate hutches, to separate the potential points of failure and limit risk. This is the classically metaphorical egg-basket distribution, or what I like to call "spatial diversity". It is by no means the only form of diversity, but certainly one of the most important in a universe with both causality and locality. Rabbits are also the very archetype of temporal diversification, aka, evolution.

For me, one of the most compelling reasons to go to space is to improve the resilience of life in general and the human race in particular. An interstellar starship represents the capability for life and humanity to be a multistar phenomenon, a significant step in ensuring the indefinite extancy of life in the universe, prelude to overcoming entropy itself. For the purpose of concision, let's henceforth call the state of humans colonizing another star system K2 (Kardeshev_Level 2).

This of course begs a definition for resilience, and a way to measure it. In materials engineering, resilience is the ability to recover from strain energy. It is the area under the linear part of the stress-strain curve.

In common parlance, resilience (of character, for instance) has a similar definition: the ability to recover from negative events, requiring some combination of (character) strength and adaptability. In materials, resilience is an energy per unit area calculated through experimental measure of elastic stress (σy) and strain (εy) limits. For the ESH state, we need to regard the collective resilience of the human species, not the resiliene of each individual. Simplistically, one could measure the total population times the distance spanned, but better Yet, that does not even come close to capturing the concept of resilience as it applies to the human collective, much less the ecological complexity that is Life. Complex systems contain diversity. There is a distribution of failure points, and the components interact and influence one another. In Scott Page's "Complexity" course, the analogy of 'landscape' is used. An easily optimizable system might look like a mountain. A less simplistic system might be like a rugged mountain range with many peaks. But a complex system is one that is constantly changing because Mt Fuji is in an arms race with Mauna Loa and every other terrain feature. This is economics and ecology. When we oversimplify our models, things like unpriced externalities can wreak havoc. For resilience, tipping points are critical. If every component of a system is uniform, then the only failure mode is catastophic like the infamous One Hoss Chaise; evolutionary improvement is impossible.

Design for Failure

In material science, fracture mechanics is a good example (I hope other materials engineers will forgive my oversimplifiation) of how defects in a crystalline structure help to arrest crack propagation by absorbing strain energy. Work hardening helps to create these defects which ultimately buffer against more catastrophic failures. In a related fashion, within linguistics the inefficiencies of a language actually serve to make it more able to convey meaning. Homonymns (words that sound alike but have completely different meaning) not only open up the field of pun humour, they provide a degree of error checking at a meta level of communication. Now, ifI haven't completely made you scratch your head at what any of this has to do with ecosystem, let me spell it out: complexity is an absolute requirement if you want resiience, it cannot be designed, but it can be designed for.