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The Cobra Effect

The cobra effect is when well-intentioned actions to achieve an aim backfire and sometimes produce the opposite effect. The story goes something like this: Back in colonial India, the top Brit in charge decided there were too many cobras around Delhi. To reduce the population, they put in place a cash reward, or bounty, for anyone who brought in a dead cobra. The intention was clear. Legend has it that people did bring in the cobras reliably because some enterprising souls had started breeding cobras for the very purpose of getting the bounty. When the authorities realised this, they scrapped the scheme, the cobra farms closed, and the bred cobras were released into the wild, significantly increasing the cobra population by a few orders of magnitude. Hence, the cobra effect: when a well-intentioned measure can have the opposite effect to that desired. It’s not clear how true this story is, but the cobra effect has been demonstrated many times. The Freakonomics podcast on the cobra effect discusses some excellent examples (with references), including: A bounty on rats in French colonial Hanoi, where the bounty was earned by bringing in a rat tail, which went the same way as the cobra story Removing wild pigs at Fort Benning, Georgia, at $40 a pig's tail, that didn’t make a dent. It's possible that the hunters would bait the pigs with all sorts of tempting scraps. Many pigs learned to avoid the hunters and instead bred like crazy while well-fed on scraps. The capital of Colombia, Bogotá, tried to reduce traffic congestion by restricting each car from driving on one day during the week. The result: people started buying more than one car and drove more on weekends. The publication of proposed areas for habitat protection to be protected for endangered species led land developers to respond by building in those areas before the land was protected. People are smart. Incentives work—in the sense that you tend to get what you incentivise. So be careful what you are incentivising. As Charlie Munger said, "Show me the incentive, and I'll show you the outcome." Related Ideas to the Cobra Effect Also see: The law of unintended consequences Goodhart’s Law Campbell's Law What gets measured gets better You get what you measure I tidied up this sketch from the original…The cobra effect is when well-intentioned actions to achieve an aim backfire and sometimes produce the opposite effect. The story goes something like this: Back in colonial India, the top Brit in charge decided there were too many cobras around Delhi. To reduce the population, they put in place a cash reward, or bounty, for anyone who brought in a dead cobra. The intention was clear. Legend has it that people did bring in the cobras reliably because some enterprising souls had started breeding cobras for the very purpose of getting the bounty. When the authorities realised this, they scrapped the scheme, the cobra farms closed, and the bred cobras were released into the wild, significantly increasing the cobra population by a few orders of magnitude. Hence, the cobra effect: when a well-intentioned measure can have the opposite effect to that desired. It’s not clear how true this story is, but the cobra effect has been demonstrated many times. The Freakonomics podcast on the cobra effect discusses some excellent examples (with references), including: A bounty on rats in French colonial Hanoi, where the bounty was earned by bringing in a rat tail, which went the same way as the cobra story Removing wild pigs at Fort Benning, Georgia, at $40 a pig's tail, that didn’t make a dent. It's possible that the hunters would bait the pigs with all sorts of tempting scraps. Many pigs learned to avoid the hunters and instead bred like crazy while well-fed on scraps. The capital of Colombia, Bogotá, tried to reduce traffic congestion by restricting each car from driving on one day during the week. The result: people started buying more than one car and drove more on weekends. The publication of proposed areas for habitat protection to be protected for endangered species led land developers to respond by building in those areas before the land was protected. People are smart. Incentives work—in the sense that you tend to get what you incentivise. So be careful what you are incentivising. As Charlie Munger said, "Show me the incentive, and I'll show you the outcome." Related Ideas to the Cobra Effect Also see: The law of unintended consequences Goodhart’s Law Campbell's Law What gets measured gets better You get what you measure I tidied up this sketch from the original

7 Jul 2019

1.5 billion heartbeats illustration: showing how mammals share broadly the same number of heartbeats from a shrew to an elephant

1.5 billion heartbeats in a lifetime

For almost all mammals, 1.5 billion heartbeats, more or less, is how much you’ve got. From the teeniest, tiniest shrew weighing just a few grams to the largest whale — passing through animals as diverse as robins, monkeys, sea lions, and giraffes — each mammal has broadly in the region of 1.5 billion heartbeats. Beyond just heart rate, knowing a mammal’s weight can help predict several other fundamental aspects of its life. A tiny mammal will likely have a heart that goes like crazy, live only briefly, and reach maturity quickly. A large animal, in contrast, will have a slow heart rate, a long life, and take its time to adulthood. The most significant outlier is us, mainly because, in recent years, we’ve significantly extended our lifetime from what would be expected from Nature. This gem, and many other fascinating insights about size, scale, Nature and physics, from the book Scale by Geoffrey West. Also see: The square-cube law…For almost all mammals, 1.5 billion heartbeats, more or less, is how much you’ve got. From the teeniest, tiniest shrew weighing just a few grams to the largest whale — passing through animals as diverse as robins, monkeys, sea lions, and giraffes — each mammal has broadly in the region of 1.5 billion heartbeats. Beyond just heart rate, knowing a mammal’s weight can help predict several other fundamental aspects of its life. A tiny mammal will likely have a heart that goes like crazy, live only briefly, and reach maturity quickly. A large animal, in contrast, will have a slow heart rate, a long life, and take its time to adulthood. The most significant outlier is us, mainly because, in recent years, we’ve significantly extended our lifetime from what would be expected from Nature. This gem, and many other fascinating insights about size, scale, Nature and physics, from the book Scale by Geoffrey West. Also see: The square-cube law

29 Jun 2019

The continental axis hypothesis

Jared Diamond’s classic book Guns, Germs and Steel, proposes some remarkable hypotheses about how the pattern of history played out, notably trying to answer the question of why it was generally the Europeans that invaded much of the rest of the world rather than the other way around. One hypothesis, striking in its simplicity if you’ve ever looked at a world map, is the significant contribution of the general orientation of the major continents. The Americas are largely lined up north–south, while Europe and Asia (Eurasia) are largely lined up east-west. An east-west alignment means the land generally has a more similar climate, day-length and seasonal variations. The general logic of the hypothesis is that the similar latitude of an east–west alignment means animals, crops, as well as travel and trade, more easily spread across the continents than across those with a north–south alignment — of the Americas and Africa — which naturally encounter more different climatic zones. As a simplified example, horses and other large animals and crops spread throughout the shared temperate latitudes of Eurasia. In contrast, South America’s only large domesticated animal, the thick-coated llama (and related species like the alpaca), couldn’t easily spread to North America through the impassable tropical barrier of the isthmus of Panama. They just aren’t built for it. There are a lot of viewpoints on the theory, and Diamond includes many more factors of geography and others — like never being able to domesticate the zebra — that go towards answering his question of why Spain invaded the Americas and not vice-versa. But ever since reading his simple hypothesis, available to anyone with a world map, I’ve found it hugely intriguing.…Jared Diamond’s classic book Guns, Germs and Steel, proposes some remarkable hypotheses about how the pattern of history played out, notably trying to answer the question of why it was generally the Europeans that invaded much of the rest of the world rather than the other way around. One hypothesis, striking in its simplicity if you’ve ever looked at a world map, is the significant contribution of the general orientation of the major continents. The Americas are largely lined up north–south, while Europe and Asia (Eurasia) are largely lined up east-west. An east-west alignment means the land generally has a more similar climate, day-length and seasonal variations. The general logic of the hypothesis is that the similar latitude of an east–west alignment means animals, crops, as well as travel and trade, more easily spread across the continents than across those with a north–south alignment — of the Americas and Africa — which naturally encounter more different climatic zones. As a simplified example, horses and other large animals and crops spread throughout the shared temperate latitudes of Eurasia. In contrast, South America’s only large domesticated animal, the thick-coated llama (and related species like the alpaca), couldn’t easily spread to North America through the impassable tropical barrier of the isthmus of Panama. They just aren’t built for it. There are a lot of viewpoints on the theory, and Diamond includes many more factors of geography and others — like never being able to domesticate the zebra — that go towards answering his question of why Spain invaded the Americas and not vice-versa. But ever since reading his simple hypothesis, available to anyone with a world map, I’ve found it hugely intriguing.

23 Jun 2019

Stop chopping board slip

Before getting started in your kitchen both Thomas Keller and Gordon Ramsay picked out this safety tip to stop your chopping board slipping while cutting. Just lightly wet a piece of kitchen towel or a tea towel and lay it flat between the surface and your chopping board. Hey presto! No slipping while cutting so all your fingers stay intact even with those tricky butternut squash.…

15 Jun 2019

The accountability ladder

The accountability ladder is a framework for taking accountability for a situation in which we can move from a powerless victim mindset to a powerful, accountable mindset. There are many ways to respond when things go wrong or need to be done. If you choose a victim mentality, it’s easy to ignore the situation, blame others for it, declare your powerlessness, or just wait and hope. Or you can consider yourself accountable and adopt a mentality of power, acknowledging the situation, owning it, looking for solutions, and taking action to do your best. Bruce Gordon explains the accountability ladder (grainy, slightly odd video) with a fun story about him and his son in which they realise his son has homework due tomorrow that’s not done. Most of us have more power over our situations and more potential for impact than we usually give ourselves credit for—whether it's our jobs, our friends, the environment, or local issues. Perhaps considering your position on the accountability ladder is a good place to start. I love this quote from Erling Kagge, the first person to walk to the Triple Poles: "Most people underestimate the possibilities you have in life. And that’s a bit sad…But don’t underestimate yourself. Also, like I said: Get up in the morning." — Erling Kagge There are many versions of the accountability ladder. I couldn’t find a definitive source. If you know, please get in touch.…The accountability ladder is a framework for taking accountability for a situation in which we can move from a powerless victim mindset to a powerful, accountable mindset. There are many ways to respond when things go wrong or need to be done. If you choose a victim mentality, it’s easy to ignore the situation, blame others for it, declare your powerlessness, or just wait and hope. Or you can consider yourself accountable and adopt a mentality of power, acknowledging the situation, owning it, looking for solutions, and taking action to do your best. Bruce Gordon explains the accountability ladder (grainy, slightly odd video) with a fun story about him and his son in which they realise his son has homework due tomorrow that’s not done. Most of us have more power over our situations and more potential for impact than we usually give ourselves credit for—whether it's our jobs, our friends, the environment, or local issues. Perhaps considering your position on the accountability ladder is a good place to start. I love this quote from Erling Kagge, the first person to walk to the Triple Poles: "Most people underestimate the possibilities you have in life. And that’s a bit sad…But don’t underestimate yourself. Also, like I said: Get up in the morning." — Erling Kagge There are many versions of the accountability ladder. I couldn’t find a definitive source. If you know, please get in touch.

8 Jun 2019

Fading affect bias

Fading affect bias is the name given to the fact that the intensity of emotion, or the affect, of our bad memories seems to fade faster than for our good memories. This means that, say, our happy memories keep us happier for longer, and our bad memories don’t affect us as much in the future. It’s called the fading affect bias, as the fading is biased more strongly for negative memories. This is handy as it naturally gives us a more positive disposition. So, for instance, after some time has passed, we may find we remember the good parts of a holiday — like an amazing beach — more clearly than the bad — like the mosquitoes at the beach. And thinking about the good parts keeps making us happy longer than thinking about the bad parts might make us sad. Brilliant! This is a different use of affect than the common affect/effect confusion.…Fading affect bias is the name given to the fact that the intensity of emotion, or the affect, of our bad memories seems to fade faster than for our good memories. This means that, say, our happy memories keep us happier for longer, and our bad memories don’t affect us as much in the future. It’s called the fading affect bias, as the fading is biased more strongly for negative memories. This is handy as it naturally gives us a more positive disposition. So, for instance, after some time has passed, we may find we remember the good parts of a holiday — like an amazing beach — more clearly than the bad — like the mosquitoes at the beach. And thinking about the good parts keeps making us happy longer than thinking about the bad parts might make us sad. Brilliant! This is a different use of affect than the common affect/effect confusion.

2 Jun 2019

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