Explaining the world one sketch at a time

Have great conversations about ideas through simple and insightful sketches.

In a Book: Big Ideas Little Pictures

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Absorb big ideas with crystal-clear understanding through this collection of 135 visual explanations. Including 24 exclusive new sketches and enhanced versions of classic favourites, each page shares life-improving ideas through beautifully simple illustrations.

Perfect for curious minds and visual learners alike.

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Hi, I'm Jono 👋

I'm an author and illustrator creating one of the world's largest libraries of hand-drawn sketches explaining the world—sketch-by-sketch.

Sketchplanations have been shared millions of times and used in books, articles, classrooms, and more. Learn more about the project, search for a sketch you like, or see recent sketches below.

Recent sketches

The Trolley Problem original variant with the runaway trolley and moral dilemma of switching the tracks

The Trolley Problem

The famous moral dilemma: switch the tracks or not? (Here's a combined version of the Trolley Problem and 3 Variants) Imagine you’re the driver of a runaway trolley whose brakes have failed. Ahead on the track, five people are working and will be killed if you do nothing. But you notice a side-track—if you switch the trolley to it, you’ll avoid the five, but one person on that track would be killed instead. Should you pull the lever and switch the tracks—killing one to save five? This is the start of the famous moral dilemma of The Trolley Problem. The fictitious scenario, and others like it, are so effective because they force us to confront our internal moral compass: what seems like the right thing to do, and why? Trolley Problem Variants As we formulate a position on a scenario, it's possible to devise variant scenarios that test our moral reasoning more sharply. For example, in the original problem, many people might suggest that it's OK for the driver to choose to save five people's lives at the expense of the one person on the other track on the basis that killing five people is worse than killing one. Where would you stand on these other variants? The Bystander at the Switch Sketch of the Bystander at the Switch Variant You’re no longer the driver. This time, you’re simply passing by when you see a runaway trolley heading toward five people. The trolley is driverless, and you’re standing next to a switch that could divert the train to another track—where one person would be killed instead. Is it morally acceptable to intervene? Does it feel different when you’re not the driver but an onlooker? The Heavy Man Problem Sketch of the Heavy Man Variant Or suppose that you were on a bridge above the track when you saw the train on its way to crash through the five people working on the track. There’s no switch—but next to you stands a very heavy man. If you push him off the bridge, his body would stop the trolley and save the five. Most people react more strongly against this version, even though the outcome is similar: one life traded for five. (This variant was originally the 'Fat Man' problem, but it's not important that the person is fat, just that they're heavy enough to stop the trolley). The Mafia Problem Sketch of the Mafia Variant Suppose once again you were the bystander at the switch passing the track in this deadly scene. This time, however, you see that the five people on the track are not workmen but hardened criminals. What's more, they've tied an innocent person to the other track. If you switch the trolley, the innocent person dies. If you do nothing, the five criminals die. Does who the people are affect your decision? How to Decide? It may be clear to you what the right path to choose is. And yet, your position may differ from someone else faced with the same scenario. The philosopher Philippa Foot introduced the Trolley Problem in a 1967 paper discussing abortion (PDF), along with several options for reasoning about it. Judith Jarvis Thomson invents some of the further scenarios (such as the mafia case) and alternative arguments in a 1985 paper, The Trolley Problem (pdf). Some possible positions and distinctions you might keep in mind include: Passive vs Active Harm Is it morally different to let five people die (by doing nothing) than to actively cause one person’s death (by switching tracks or pushing someone)? Are you killing or are you failing to save? Is there a difference in what we do and what we allow? Negative Duties vs Positive Duties Some argue there’s a moral difference between duties not to harm (negative duties) and duties to help (positive duties). Avoiding Injury vs Bringing Aid Is there a difference when you are making choices that save different numbers of people rather than making choices where people will die as a direct result of your choices? For example, suppose you face a choice of rescuing a large group of people while leaving another small group to die. Or what if a villain asked you to sacrifice an innocent person, or they will kill five others. Rights vs Utility Does your action violate someone’s rights? Even if the outcome is better overall, is it acceptable to use a person as a means to an end? Is it a matter of degrees? For example, violating an individual's rights by pushing them off a bridge versus stealing from them as a route to save someone. Doctrine of Double Effect Philippa Foot discusses the Doctrine of Double Effect—that our actions may have intended consequences and other outcomes that are foreseeable but not intended—the distinction between "direct" and "oblique intention". In the case of the runaway trolley, it's "one thing to steer towards someone foreseeing that you will kill him and another to aim at his death as part of your plan." Or, for example, in surgery to save a mother during childbirth, the death of a child may be foreseen but not intended. Dilemmas While fictitious moral dilemmas are intriguing thought experiments, real dilemmas surround us. A general orders his troops on a dangerous mission. Adjusting the speed limit on a dangerous road. People die from driving too fast, but walking isn't an option—what's the appropriate risk of death we're comfortable with? Who should receive aid? Who should be rescued first? Should a pilot steer a plane that's about to crash into a less populated area? I remember, in the film Beneath Hill 60 (spoiler), a commander must decide whether to detonate underground munitions to execute the battle plan, knowing that one of his team members is trapped. I find moral dilemmas to be at once fascinating, puzzling, troubling, and uncomfortable. Related Ideas to the Trolley Problem The Front Page Test Equality and Equity The Prisoner's Dilemma Learn More About the Trolley Problem You can, and should, have fun with absurd trolley problems at the brilliant neal.fun—and also see what other choices people made In Michael Sandel's course and book, Justice, he discusses the trolley problem and many other difficult questions of ethics and morals and how to reason about them Both Philippa's and Judith's original papers are quite readable: Philippa Foot, The Problem of Abortion and the Doctrine of the Double Effect (PDF) Judith Jarvis Thomson, The Trolley Problem (PDF) Prints of the Trolley Problem Trolley Problem standalone prints Trolley Problem and Variants prints
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Looking back in time as we look to the stars: A visual explanation of how light from the Moon, Sun, stars, and galaxies shows us the past because light takes time to travel.

Looking Back in Time: The Speed of Light and the Night Sky

The speed of light is a mighty ~300,000 km/s. But even at that speed, because the distances in space are so vast, sometimes it has to settle in for the ride. When we see the light from a distant star or galaxy, we're not seeing it as it is now—we're seeing it as it was when the light first left on its journey to Earth. Why Looking at Stars Is Like Looking into the Past When you hear a thunderclap after seeing lightning, you know that you're hearing something that happened some time ago. Looking into the night sky is similar—except here, it's light that causes the delay, not sound. Take the moon, for instance. At a little under 400,000 km away, light that has reflected off the moon takes around 1.3 seconds to reach us. But the sun is much further. At around 150 million km away, it takes a little over 8 minutes for light from the sun to reach us. So what we are seeing at the sun, for example, a solar flare, happened 8 minutes ago. (The distance from the sun to Earth is called 1 AU - Astronomical Unit). As soon as you look at more distant objects, you realise that looking up at the night sky is looking way back in time. To measure these distances, we use light years—the distance light travels in one year. So, the number of light years an object is away from us is how far back in time we are seeing. Our nearest star system is Proxima Centauri at around 4.24 light-years away. What we see on Proxima Centauri happened over four years ago. Here are a few stars you can spot at night (in the northern hemisphere) and how long ago the light from each started its journey: Polaris (the North Star): 433 years ago, around 1590 AD Pleiades (Seven Sisters): 444 years ago, around 1580 AD Betelgeuse: 548 years ago, around 1480 AD Put another way, if you were in Betelgeuse right now, you’d be looking at light from our sun around the time Leonardo da Vinci was pioneering sketchplanations. The Andromeda Galaxy, the nearest spiral galaxy to our Milky Way, is a staggering 2.5 million light-years away. This means the light we see from Andromeda today set off on its journey 2.5 million years ago — around the beginning of the Pleistocene, the most recent ice age era, when early mammoths and sabre-toothed cats were emerging. Seeing the Early Universe As we look with increasingly larger telescopes at more distant objects, scientists gather clues about the Universe's earliest days. The farther we look, the farther back in time we see. In 2024, the James Webb telescope detected a galaxy so far away that the light we see started travelling when the Universe was just 2% of its current age. So, as you look up in the sky, it's also like looking at a map of different times. Crazy. Related Ideas to Looking Back in Time Find the North Star Use the Southern Cross to find south Solar system planets: how big is the solar system? Redshift Orbit Point Nemo Antipodes Super moon The Overview effect Comets, Asteroids, Meteors, and Meteorites: know your space objects The Flash-to-Bang Method for estimating the distance of lightning The Doppler effect
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John Muir quote illustration: I only went out for a walk, and finally concluded to stay out till sundown, for going out, I found, was really going in — John Muir quote

Going Out Was Really Going In — John Muir Quote

John Muir is one of my heroes. A Scotsman who moved to California, and through his writings and public engagement (in his later years), played a direct role in America's Greatest Idea: the creation of the National Park system. He wrote prodigiously and is very quotable. The National Park Service has a lovely page of inspiring John Muir quotes, as does the Sierra Club he founded, with sources. But most of all, he spent long days and years by himself exploring the Sierra Nevada mountains of California and taking in everything that Nature offered. Drawn from his later writings and published in John of the Mountains: The Unpublished Journals of John Muir, 1938, is this wonderful quote: "I only went out for a walk, and finally concluded to stay out till sundown, for going out, I found, was really going in." — John Muir I'm sure people draw their own value from this quote. But for me, it reminds me that we are part of Nature and belong outside, not in. Is there some out that you can make your in this week? -- The quote appears on pages 427 and 438 of the copy in the wonderful Internet Archive. Or some rare copies are available to order. An eye-opening and readable view into John Muir's writings is his book My First Summer in the Sierra, about the year he spent driving sheep up into the mountains and living alongside them. It gives an early taste of his poetic writing, the wild life he embraced, complete with remarkable stories, and the raptures the mountains produced in him. Among others, My First Summer in the Sierra includes the lovely quote (also sketched): "As soon as we take one thing by itself, we find it hitched to everything else in the universe." John Muir's life and writings have had some reevaluation in recent years, see, for instance, this piece from the Sierra Club after the murder of George Floyd in May 2020. I recommend reading Muir's writing for yourself. The backdrop is from Upper Grove in Mariposa, Yosemite. Related Ideas to Going Out was Really Going In Also see: Rückenfigur Hitched to Everything Else in the Universe The 3-Day Effect 5 Ways to Wellbeing Forest Bathing Time hierarchy How to Instantly Feel Better Truth and Beauty
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What is a halfpinion with example of someone arguing for the benefits and another arguing the costs are too high. It's not a real opinion unless it considers both. Term from Scott Adams.

Halfpinion: considering only the benefits or the costs

Governing sometimes seems easy from afar. We should spend more on education. We should pay hospital staff more. We should fix the roads. More police. Everyone should work harder. These would all be great if they were free. Unfortunately, doing more in one area often means taking from another. What is a Halfpinion? The reality is that most actions have benefits and costs. A halfpinion is a handy term for when someone is ignoring one half of a topic—either the costs or the benefits. When you only consider one side of an issue, often just the benefits, you don't have a full opinion, you just have a halfpinion, and can't make an informed decision. Getting a pet, having a child, moving to the country, working remotely, working in-house versus working at an agency, going freelance, banning plastics, staying up all night, or launching a new feature — each of these has benefits and also costs. It applies to values, too. If your company values speed, it might mean that you have to accept that not everything will be perfect. If you value quality, it won't always be the cheapest. Valuing speed while tacitly assuming that quality won't be affected is a halfpinion. If you don't consider both aspects, you might find the grass isn't always greener. Providing a credible perspective requires comparing the full benefits of a choice to the full costs. Now, you don't have to accept a trade-off—the benefits or the costs, or somewhere in between. In design, I learned that we innovate through resolving contradictions. In the progression of ideas, this might follow thesis, antithesis, synthesis. Perhaps there's a creative solution to be found that gets the benefits without most of the costs. But considering only one or the other is just a halfpinion. Related Ideas to Halfpinion Also see: Confirmation bias Features are like pets The Priority No: saying yes, as long as we drop something else (one of Judd Antin’s three types of “no”) Feedback analysis: predicting, comparing and learning Halfalogue: hearing only one side of a conversation Halfpinion is a term coined by Scott Adams. I read about it in his book Loserthink. An example he gives is one group of people saying, "We can't do this, it's too expensive," and another responding, "But children are our future." The groups aren't so much disagreeing as pointing out one side of the issue: children are our future, and education is expensive.
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Congested equilibrium and how suppressed journeys and latent demand build-up means you can't build your way out of congestion

Congested Equilibrium

You, like me, probably dislike being stuck in traffic. If you live in a densely populated area, it's likely that for at least some of the day, a number of the major roads around you are congested, i.e. there's a lot of traffic, and it tends to go slowly. Unfortunately, as I learned with the phrase "Congested equilibrium," from UCL Professor David Metz, there's no magic wand to wave for roads that will run smoothly and get you to your destination with minimal hassle. What is Congested Equilibrium? It's easy to assume that there's a fixed amount of traffic on the roads. So if your local road agency widens, improves, or adds alternative fast roads to get to your destination, you might think that traffic will improve. And it does, but only briefly. Then somehow the traffic jams return. The reality is that in densely populated areas, traffic congestion tends to be self-regulating. When driving is slow and somewhat painful, people who would have driven make other choices: choose not to travel—maybe a video call instead, or just don't go to the shops take a different means of transport such as a train or bike travel earlier or later take different routes After millions in road investment—perhaps widening roads or building a bypass or extended stretch of motorway—traffic runs faster, for a time. But when people realise that roads are again a good option for travel, some of those who had chosen not to drive or didn't use that route before, jump back in the car and make use of the new, improved roads. And the increased traffic once again leads to congestion that gets progressively worse until people decide to make other choices once again. Traffic congestion is a feature of road networks that is very hard to avoid because densely populated areas have a vast reserve of these suppressed trips—people who would drive if the traffic was better—ready to make use of an improved road network when it arrives. From congested equilibrium comes the maxim in travel planning circles: "You can't build your way out of congestion." I learned about congested equilibrium and the general trials and challenges of travel planners in the book Good to go? Decarbonising Travel After the Pandemic by Professor David Metz. Although the book had less to do with decarbonising than I expected, it did teach me a great deal about the challenges and considerations of travel planning. Related Ideas to Congested Equilibrium Marchetti's Constant—as we travelled faster, we travelled farther, maintaining about an hour's daily travel time Laws of Expansion Isochrones Pollution is highly localized: take the back streets Travel choices in London Our Senses are Built to Take in Information at Human Pace Jevons paradox Cobra effect Frequency is freedom, a line from Jarrett Walker about the impact of frequency on public transport. I haven't sketched this yet, but it's so catchy I thought I'd share More I learned About Traffic For the last half a century or so, the average daily travel time has remained unchanged. This is despite huge investments in road networks in urban areas. When I find myself stuck in and complaining about traffic, my mind flashes back to a memory of a billboard in San Francisco that read, "You are not stuck in traffic. You are traffic." Then I feel better about my fellow drivers. What people like least is uncertainty about journey time. So digital navigation, as exemplified by Google Maps, is doing an amazing job at giving us peace of mind here. Until ChatGPT, I put Google Maps as the best app out there. In European cities you tend to find either high public transport use (like London), or a lot of cycling (think Copenhagen). But you don't tend to find high levels of both. Copenhagen's proportion of car journeys is similar to London's. The car has an appeal when the roads allow it. Improving cycling tends to pull people from public transport and vice versa rather than pull people from their cars. Of David Metz' points that stick with me is also that the most effective way to reduce car usage in city centres, in conjunction with improving other means of travel, is to reduce the availability of parking. Also, each city is different: some cities like London are spread wide and the distances are large, some have more cooperative weather, some have a lot of hills, and some are in countries where cars are a significant status symbol. There's no one-size-fits-all.
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Calm like a duck quote showing a duck who's calm on the surface, but under the water, I'm paddling like hell. Also, a Michael Caine quote

Calm Like a Duck

Before our first child was born, we attended a series of classes with other expecting couples. The class aimed to prepare us for the joys and challenges of childbirth and the life changes that come with becoming parents. Most parents-to-be were feeling a little anxious. One dad, though, never seemed fazed—he stayed cool through everything. At one point, I asked him how he was so relaxed. He said, "I'm calm like a duck. On the surface, I'm gently floating, but under the water, I'm paddling like crazy." It's over 10 years ago now, but I remember it clearly. It stuck with me for two reasons. First, it's a brilliant analogy for calmness—the two halves of a duck—and makes for a funny picture, which is why I thought it deserved a sketch. Second, it reminds me that when I'm in a stressful situation or feeling nervous, it's easy to look around and see people who seem calm and confident. And if I start thinking I'm the only one feeling anxious, it usually makes it worse. However, when I recall this story, I remember that just because someone looks calm, it doesn't mean they feel calm. They might be "calm like a duck." Under the surface, their legs may be waggling furiously, just like I'm feeling. Michael Caine, in his 2018 book Blowing the Bloody Doors Off: And Other Lessons in Life, said: "Ducks look calm as they glide along the surface of the water but they're paddling like hell underneath. When you're doing your preparation right, it sometimes looks so good that people watching you make the mistake of assuming it's all natural and effortless. In my experience, it never is." In some ways, this misconception is everywhere when we see high performers who make things look easy: A finished book without all the awful first drafts A polished theatre performance without the chaos of rehearsals A calm statement from a leader without the deliberation or doubt that led to it A marathon finish, without the 6 am runs they didn't want to do As a leader, it can help to offer a calm demeanour, but don't mistake the appearance of calm for having everything sorted out. We all have to work hard through times that aren't easy if we want to do great things—even ducks. And Michael Caine. Related Ideas to Calm Like a Duck The First Draft is Always Perfect The Doorstep Mile One in a Row The Best Writing is Re-writing Don't Compare Your Back of House with Others' Front of House Front Stage - Back Stage The excellent QI looked into the source of this quote and had it down to the Japanese practice of duck diplomacy.
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