Explaining the world one sketch at a time

Simplifying complex ideas through fun and insightful sketches. Explore topics from science, creativity, psychology, and more explained in pictures.

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Recent sketches

Hump-back stations

A rather clever way of capturing energy as vehicles slow down is to store the energy you'd use in braking as gravitational energy. This way of storing energy is used on a number of central London underground stations by constructing the stations at the top of a small hill in the track. Once built, the hump-back-station design has the handy effect of naturally slowing trains down as they approach a station and naturally accelerating them as they leave a station. Apparently, on London's Victoria line this saves 5% in energy and helps the trains run 9% faster. You're not always going to be able to put a slope just where you need to slow down, unfortunately. However, it makes a ton of sense for pedestrian crossings where raising the crossing to the level of the payment means pedestrians don't have kerbs to negotiate and cars are naturally encouraged to slow down. Victoria line data from Sustainable Energy without the Hot Air, by the late David JC MacKay…A rather clever way of capturing energy as vehicles slow down is to store the energy you'd use in braking as gravitational energy. This way of storing energy is used on a number of central London underground stations by constructing the stations at the top of a small hill in the track. Once built, the hump-back-station design has the handy effect of naturally slowing trains down as they approach a station and naturally accelerating them as they leave a station. Apparently, on London's Victoria line this saves 5% in energy and helps the trains run 9% faster. You're not always going to be able to put a slope just where you need to slow down, unfortunately. However, it makes a ton of sense for pedestrian crossings where raising the crossing to the level of the payment means pedestrians don't have kerbs to negotiate and cars are naturally encouraged to slow down. Victoria line data from Sustainable Energy without the Hot Air, by the late David JC MacKay

28 Nov 2021

Time hierarchy

Durable dynamic systems have elements, or layers, that change at different rates. The fast layers that change quickly provide the innovation, while the slower layers stabilise and remember. In his short article Pace Layering: How Complex Systems Learn and Keep Learning, Stewart Brand gives this evocative example of the time hierarchy of a coniferous forest: "Take a coniferous forest. The hierarchy in scale of pine needle, tree crown, patch, stand, whole forest, and biome is also a time hierarchy. The needle changes within a year, the crown over several years, the patch over many decades, the stand over a couple of centuries, the forest over a thousand years, and the biome over ten thousand years. The range of what the needle may do is constrained by the crown, which is constrained by the patch and stand, which are controlled by the forest, which is controlled by the biome. Nevertheless, innovation percolates throughout the system via evolutionary competition among lineages of individual trees dealing with the stresses of crowding, parasites, predation, and weather. Occasionally, large shocks such as fire or disease or human predation can suddenly upset the whole system, sometimes all the way down to the biome level." It's an example of his wonderful framework of pace layers which he applies as the working structure of a robust and adaptable civilisation.…Durable dynamic systems have elements, or layers, that change at different rates. The fast layers that change quickly provide the innovation, while the slower layers stabilise and remember. In his short article Pace Layering: How Complex Systems Learn and Keep Learning, Stewart Brand gives this evocative example of the time hierarchy of a coniferous forest: "Take a coniferous forest. The hierarchy in scale of pine needle, tree crown, patch, stand, whole forest, and biome is also a time hierarchy. The needle changes within a year, the crown over several years, the patch over many decades, the stand over a couple of centuries, the forest over a thousand years, and the biome over ten thousand years. The range of what the needle may do is constrained by the crown, which is constrained by the patch and stand, which are controlled by the forest, which is controlled by the biome. Nevertheless, innovation percolates throughout the system via evolutionary competition among lineages of individual trees dealing with the stresses of crowding, parasites, predation, and weather. Occasionally, large shocks such as fire or disease or human predation can suddenly upset the whole system, sometimes all the way down to the biome level." It's an example of his wonderful framework of pace layers which he applies as the working structure of a robust and adaptable civilisation.

21 Nov 2021

Flotsam and jetsam

I'd never heard the words flotsam and jetsam used in any way but together so had always assumed it was a term to mean general debris floating in the water or washed up. It turns out they have distinct meanings that also affect how they're treated by law. Flotsam, from flotter to float, refers to debris accidentally lost or washed overboard, often from a shipwreck or accident. Jetsam is debris that was deliberately jettisoned by a boat in distress, likely to try and lighten the load. Being that flotsam was lost accidentally, under maritime law, it can be claimed by the original owner, but jetsam can be claimed by the person who found it. The rubber duck in the sketch refers to the story of the thousands of rubber ducks that washed overboard (flotsam) in the Pacific ocean in 1992. Over the next 25 years, the ducks found themselves washed ashore all across the world revealing much of the ocean's currents as one giant connected system. More on flotsam and jetsam…I'd never heard the words flotsam and jetsam used in any way but together so had always assumed it was a term to mean general debris floating in the water or washed up. It turns out they have distinct meanings that also affect how they're treated by law. Flotsam, from flotter to float, refers to debris accidentally lost or washed overboard, often from a shipwreck or accident. Jetsam is debris that was deliberately jettisoned by a boat in distress, likely to try and lighten the load. Being that flotsam was lost accidentally, under maritime law, it can be claimed by the original owner, but jetsam can be claimed by the person who found it. The rubber duck in the sketch refers to the story of the thousands of rubber ducks that washed overboard (flotsam) in the Pacific ocean in 1992. Over the next 25 years, the ducks found themselves washed ashore all across the world revealing much of the ocean's currents as one giant connected system. More on flotsam and jetsam

14 Nov 2021

The rule of 7

The rule of 7 is an idea in marketing that it can take hearing a message 7 times before we might take action. Apparently the rule is from early movie marketing and while I don't know if I'd rely on the number it certainly seems a sensible idea to keep in mind that you can't expect people to take action the first time they hear your message — if you're trying to get people to try something new be it buying food, downloading your app, watching a movie, or a choosing an electric car, it takes a while and repeated exposure before you can expect it to pay off. I can't remember where I heard it, but some advice I keep in mind when communicating is that by the time you're tired of saying it, others are just starting to hear it. It's not a bad thing to repeat your main message. I learned about the Rule of 7 from the recent book Human Powered by Trenton Moss. When putting an apple in the adverts on this sketch I was reminded that so often it's the things in the supermarket that are most healthy for us that don't get anyone shouting about them at all.…The rule of 7 is an idea in marketing that it can take hearing a message 7 times before we might take action. Apparently the rule is from early movie marketing and while I don't know if I'd rely on the number it certainly seems a sensible idea to keep in mind that you can't expect people to take action the first time they hear your message — if you're trying to get people to try something new be it buying food, downloading your app, watching a movie, or a choosing an electric car, it takes a while and repeated exposure before you can expect it to pay off. I can't remember where I heard it, but some advice I keep in mind when communicating is that by the time you're tired of saying it, others are just starting to hear it. It's not a bad thing to repeat your main message. I learned about the Rule of 7 from the recent book Human Powered by Trenton Moss. When putting an apple in the adverts on this sketch I was reminded that so often it's the things in the supermarket that are most healthy for us that don't get anyone shouting about them at all.

7 Nov 2021

Sonic boom

Sonic booms are the noise heard when an object travels at or faster than the speed of sound. As an object travels through the air it pushes air out of the way creating a shockwave — like the wake of a boat. If you were traveling fast in a plane you can imagine that as the shockwaves move away from you at the speed of sound (around 340 m/s), because you're traveling too, the ones in front of you compressed together a little. As you reach the speed of sound, you're now traveling as fast as the shockwaves and they all bunch up forming a strong pressure wave. An object traveling faster than the speed of sound leaves its shockwaves behind it in a cone-shape called a Mach cone after Ernst Mach. To an observer on the ground the sudden change in pressure as the pressure wave passes is experienced as a loud boom. There's quite a lot of subtlety to sonic booms and we're still researching technology to reduce them to make faster than sound travel less, well, noisy.…Sonic booms are the noise heard when an object travels at or faster than the speed of sound. As an object travels through the air it pushes air out of the way creating a shockwave — like the wake of a boat. If you were traveling fast in a plane you can imagine that as the shockwaves move away from you at the speed of sound (around 340 m/s), because you're traveling too, the ones in front of you compressed together a little. As you reach the speed of sound, you're now traveling as fast as the shockwaves and they all bunch up forming a strong pressure wave. An object traveling faster than the speed of sound leaves its shockwaves behind it in a cone-shape called a Mach cone after Ernst Mach. To an observer on the ground the sudden change in pressure as the pressure wave passes is experienced as a loud boom. There's quite a lot of subtlety to sonic booms and we're still researching technology to reduce them to make faster than sound travel less, well, noisy.

31 Oct 2021

Primary metaphor

One of the few books I've read all in one sitting is Metaphors We Live By, by George Lakoff. It was so fascinating learning how some of the most fundamental concepts we use to govern our lives are understood through metaphor. For example, one understanding of time is through our experience of space, so it seems natural to say, the hard times are behind us, or, I'm looking forward to the future. Or that Ideas Are Objects so you can give someone an idea, or toss a few ideas around. Or that Understanding Is Grasping, so you can get the idea, or get to grips with a concept. Primary metaphor is a theory of how these metaphorical understandings may form when we're young as we associate abstract ideas with direct experience. So it's natural that, when we're young, important things are often big and can exert control over us, leading to Important Is Big — Tomorrow's a big day, it's just a little thing, It was a huge deal. Or experiencing warmth when we feel affection leading to Affection Is Warmth — he greeted me warmly, she gave me the cold shoulder. Or how sometimes to know something is to see something, such as when we find out what's in a box by seeing what's in a box, leading to Knowing Is Seeing — I see what you mean, that's clear to me know, I'm feeling in the dark on that, let's shed some light on the matter. Other examples of primary metaphor from Philosophy in the Flesh by Lakoff and Johnson include: More Is Up — from seeing things increase in height when there is more of them eg the prices are rising Difficulties Are Burdens — from difficult things literally being harder to deal with eg I'm feeling a bit weighed down at the moment States Are Locations — from associating experiences with actual places eg I'm in a rut right now, but I'll get out of it. Bad Is Stinky — from bad things actually smelling bad eg that movie stinks Purposes Are Destinations — from achieving goals when we get somewhere such as having a drink eg I'm going to be a star but I'm not there yet There are many more, plus the whole world of metaphor guiding how we construct our place in the world is fascinating. The theory of primary metaphor is from Joseph Grady. If the gif is annoying here are individual static images (and prints) for: Primary metaphor (print), Knowing Is Seeing (print), Affection Is Warmth (print) …One of the few books I've read all in one sitting is Metaphors We Live By, by George Lakoff. It was so fascinating learning how some of the most fundamental concepts we use to govern our lives are understood through metaphor. For example, one understanding of time is through our experience of space, so it seems natural to say, the hard times are behind us, or, I'm looking forward to the future. Or that Ideas Are Objects so you can give someone an idea, or toss a few ideas around. Or that Understanding Is Grasping, so you can get the idea, or get to grips with a concept. Primary metaphor is a theory of how these metaphorical understandings may form when we're young as we associate abstract ideas with direct experience. So it's natural that, when we're young, important things are often big and can exert control over us, leading to Important Is Big — Tomorrow's a big day, it's just a little thing, It was a huge deal. Or experiencing warmth when we feel affection leading to Affection Is Warmth — he greeted me warmly, she gave me the cold shoulder. Or how sometimes to know something is to see something, such as when we find out what's in a box by seeing what's in a box, leading to Knowing Is Seeing — I see what you mean, that's clear to me know, I'm feeling in the dark on that, let's shed some light on the matter. Other examples of primary metaphor from Philosophy in the Flesh by Lakoff and Johnson include: More Is Up — from seeing things increase in height when there is more of them eg the prices are rising Difficulties Are Burdens — from difficult things literally being harder to deal with eg I'm feeling a bit weighed down at the moment States Are Locations — from associating experiences with actual places eg I'm in a rut right now, but I'll get out of it. Bad Is Stinky — from bad things actually smelling bad eg that movie stinks Purposes Are Destinations — from achieving goals when we get somewhere such as having a drink eg I'm going to be a star but I'm not there yet There are many more, plus the whole world of metaphor guiding how we construct our place in the world is fascinating. The theory of primary metaphor is from Joseph Grady. If the gif is annoying here are individual static images (and prints) for: Primary metaphor (print), Knowing Is Seeing (print), Affection Is Warmth (print)

24 Oct 2021

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