Veritasium explores the Prisoner's Dilemma and Axelrod's tournaments, showing why tit-for-tat and forgiving strategies win in repeated games. It extends the ideas to cooperation in evolution and conflict.
Why Hacker News points people here: HN commenters reach for it constantly as an approachable explanation of why cooperation and reciprocity are rational strategies.
“Veratasium just made an approachable video on this subject recently, I definitely recommend.”HN comment, 2024
“Veratasium just made an approachable video on this subject recently, I definitely recommend.”
Approachable video rebutting fears that cooperation is impossible long term.
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Veratasium just made an approachable video on this subject recently, I definitely recommend. It rebukes the whole 'oh no I just heard what a Nash equilibrium is and now I'm worried cooperation is impossible long term' fears some people interpret his thought experiment (prisoners dillema) to have. Tldr it's rare that you can't coordinate, communicate, or have exactly one trial. this video
Strongly recommendspants2Apr 2026
“This Veritasium video is excellent, and makes the argument that there is something intrinsic in mathematics (game theory) that encourages prosocial behavior.”
This Veritasium video is excellent, and makes the argument that there is something intrinsic in mathematics (game theory) that encourages prosocial behavior. this video
RecommendsninkendoDec 2023
“Veritasium had a great video on this very topic today, in fact”
Covers the prisoner's dilemma and cooperation, relevant to crown shyness.
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The way I’ve always imagined crown shyness (from a total less-than-layman perspective where I’ve only casually read about the topic) is from a game theory/selfish gene perspective. Trees of the same species will share a lot of the same genes, and genes that code for non-shyness will grow to the detriment of the trees around them. Trees which critically are very likely to share a lot of the same genes. So that non-shyness gene will lose out in the long run against genes that code for shyness. It’s similar to the prisoner’s dilemma, with shyness being “cooperate” and non-shyness being “defect”. Groups of trees with cooperative strategies would do better collectively (and win out), even if a non-cooperative individual can beat a cooperative individual every time. Veritasium had a great video on this very topic today, in fact: this video
RecommendsaeonikDec 2023
“Veratasium's video brings me some modicum of hope at least”
Offers some hope about cooperation and the prisoner's dilemma.
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After watching this video, Veratasium's video brings me some modicum of hope at least: "What The Prisoner's Dilemma Reveals About Life, The Universe, and Everything" this video Practice spotting those cognitive biases. Your Wikipedia rabbit hole may start here: link
Recommends0wisJan 2024
“I found it best explained in the Veritasium video on game theory”
Best explanation of how game theory favors empathy but not too much.
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According to game theory, you should have empathy but not too much. Its such a powerful theoretical finding for every aspect of life. I found it best explained in the Veritasium video on game theory [1] [1]: this video
RecommendstravisgriggsMar 2024
“I really enjoyed Veritaseum’s recent take on the “Prisoners Dillema” and Game Theory”
Covers the value of forgiving in game theory simulations with a good history.
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To start with, I really enjoyed Veritaseum’s recent take on the “Prisoners Dillema” and Game Theory ( this video ). It seems appropriate to mention since it circles around this same “dillema” and even places a numerical value on the value of forgiving in game theory simulations. The historical part and layman’s reduction is good to. I think THIS article undersells the “Hold a Grudge” payoff: > David feels justified but might damage the relationship and stop Samantha from learning from her mistake. Most relationships have an ongoing bargaining element to them. Exchange of services, tit for tat, quid pro quo, pay each others backs, etc. Even when we pretend they don’t, or obscure them by wrapping higher level words around them. What makes forgiving hard, is that when we feel wronged, we feel it gives us a better bargaining position go forward. If we forgive, we fear it devalues or weakens our bargaining power going forward. Why else are we so tempted in a debate to rejoin with “yeah, well you do <fill in the blank wrong thing> too!” To clarify, I AM a big fan and proponent of forgiveness. I aspire to be better at. But I think this article has missed a key part of the dillema, by not better portraying the real allure of not forgiving.
RecommendsbraiampDec 2024
“Veritasium did a piece about it for explaining for layman.”
Layman explanation of tit for tat and when it works.
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Tik for tat exists, but only when you can have a clear communication about it. Veritasium did a piece about it for explaining for layman. this video
RecommendstiffanyhMay 2025
“Vertasium has a great video talking how Tit-for-Tat (Copycat) wins as a strategy”
Shows how tit-for-tat wins and describes the original strategy competition.
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Vertasium has a great video talking how Tit-for-Tat (Copycat) wins as a strategy (and how there was a math competition that proved it as well) this video --- This seems like a nice rebuild of the math competition performed years ago (as talked about in the video link above). Direct link to that part of the video: this video
RecommendsSammiJul 2025
“Actually Veritasium has a great video about this. It's proven as the most effective strategy in monte carlo simulation.”
Shows giving others a chance is the most effective strategy in simulation.
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You don't have to go as far as to straight up "trust by default". You can instead "give a chance" by default, which is the middle path. Actually Veritasium has a great video about this. It's proven as the most effective strategy in monte carlo simulation. EDIT: This one: this video
Recommendstrinsic2Feb 2026
“There is a video about game theory [0] that describes this problem very clearly.”
Explains how stepping outside direct escalation yields better outcomes.
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> it's no longer a matter of choice, you have to do it too You know, there are plenty of examples where people in positions of power choose different paths of escalation. I doesn't always need to be liner tit for tat. Some times you need to step back and look at the larger picture and decide of the escalation is worth the risk for all of humanity. There is a video about game theory [0] that describes this problem very clearly. You have better outcomes when you make decisions outside the direct course of escalation. Please don't talk in absolutes about these things, you have an opinion. I accept that, but its not as black and white as you think [0]: this video
Cites itrockbrunoMar 2024
“Relevant video”
Relevant to how some people doing the right thing keeps society going.
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Humanity has had people who did not care about doing the right thing since forever, and still we thrived. As long as someone is doing the right thing, we're on the right track. Relevant video: this video
Cites itpassion__desireAug 2024
Inspired the idea of simulating human-like features in prisoner's dilemma strategies.
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Can you ask the agents to be lenient, or stringent or forgetful or forgiving ? And then have one group who participate in decision play against other group. The groups will have distribution of the properties I laid out before or other interesting properties. I have been desiring to know what would human like features do to prisoners dilemma strategies after watching veritasium video. What Game Theory Reveals About Life, The Universe, and Everything this video
Cites itrramadassFeb 2025
“Veritasium's video on Game Theory and Axelrod's tournaments”
Covers Axelrod's tournaments, cited among a list of sources.
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You are not quite right and there are "organized groups" active on HN influencing sensitive topics. The equivalence you are making i.e. "society is divided, the HN community is a reflection of the society and therefore the community is divided" does not say anything about how specific groups may exploit the situation and push their agenda. They are not all rational actors nor is it a zero-sum game. To understand what i mean take a look at; 1) Nassim Taleb's book Skin in the Game - link . Specifically his The Minority Rule which basically states that an intransigent minority can almost always prevail over a flexible majority. It is the asymmetry which is being used to game the system. Nassim Taleb's article The Most Intolerant Wins: The Dictatorship of the Small Minority - link Nassim Taleb & Naval Ravikant video on The Minority Rule - link 2) Also see Game Theory( link ) and the books The Evolution of Cooperation ( link ), The Complexity of Cooperation( link ) by Robert Axelrod Veritasium's video on Game Theory and Axelrod's tournaments - this video Influence decision models: From cooperative game theory to social network analysis - link A Survey of Game Theory as Applied to Social Networks - link
Cites itconartist6Mar 2025
Tit for tat explains why anger can be a sensible strategy.
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> The central puzzle is this: the payback idea does not make sense. Whatever the wrongful act was – a murder, a rape, a betrayal – inflicting pain on the wrongdoer does not help restore the thing that was lost. My understanding is that the "tit for tat" algorithm explains why anger can make sense as a game theory strategy. this video
Cites itbabyApr 2025
“After watching the tit-for-tat video of Veritasum[1] I agree with America's strategy”
Used to justify reciprocal tit-for-tat policy toward Chinese apps.
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The US is lying about tiktok, the only reason is to mirror China's strategy towards American app. After watching the tit-for-tat video of Veritasum[1] I agree with America's strategy of banning Chinese apps until China allows American apps. That being said, I wish the US was more transparent about why they're doing this instead of lying. I'm guessing the reason why they're lying is that they don't want to scare ALL Chinese companies. [1]: this video
Cites itptrhvnsAug 2025
“tit-for-tat with a little extra forgiveness to break downward spirals is a little better.”
Tit-for-tat with a little forgiveness does better.
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If Veritasium ( this video ) is right, tit-for-tat with a little extra forgiveness to break downward spirals is a little better.
Cites itschneemsAug 2025
“The somewhat counterintuitive rules for the best expected strategy to repeated conflicts”
Lists the rules for best strategy in repeated conflicts, at 15:00.
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The somewhat counterintuitive rules for the best expected strategy to repeated conflicts: - Nice - Friendly - Retaliatory/provokable - Clear this video At 15:00 in.