Key Takeaways
A big theme in one glance
This article walks through mental models, classic philosophy, modern rationality projects, digital “wisdom” products, and even a short Dutch language lesson, to show how many small ideas can slowly change the way a mind works.
Old books, new bundles
Modern bundles like “100 Mental Models,” “Think Better,” “Productize Yourself,” or “Learn Value” often repackage ideas that already live in classic works by Plato, Aristotle, Bacon, Nietzsche, Gibbon, Adam Smith, the Stoics, and modern psychology and economics.
Curators of thinking
Projects such as Farnam Street, LessWrong, The Rabbit Hole, and The Latticework collect models and insights from many fields, making it easier to build a personal “latticework of mental models” that supports clearer decisions.
Practical levers for daily life
Tools like second-order thinking, antifragility, skin in the game, pre-mortems, OODA loops, ethical persuasion, growth mindset, and Stoic practice help in real decisions under uncertainty, not just in theory.
Stories, language, and “quirks” as models
Narrative tricks (breaking the fourth wall), comedy series, and ordinary language exchanges such as a Dutch promise not to lose a key all act as mental models: they show how people see reality, make meaning, and misread one another.
Playing long games
Long learning, not quick hacks, creates compounding returns. Angel investors like Naval Ravikant, curators like Shane Parrish, and readers like Blas Moros show what happens when reading, reflection, and disciplined experimentation are treated as a decades-long game.
Story & Details
Digital “wisdom” shops and the promise to upgrade your mind
Online shops on platforms like Gumroad sell digital bundles that promise to improve thinking: “100 Mental Models,” “Think Better,” “Productize Yourself,” and “Learn Value” are typical titles. They often include ebooks, long audiobooks, flashcards, quotes, “mental maps,” worksheets, checklists, and libraries of public-domain classics such as Meditations, The Autobiography of Benjamin Franklin, The Art of War, On the Origin of Species, and The Wealth of Nations.
Gumroad itself is a simple platform where independent creators upload digital files, set prices, and sell them directly to buyers. It handles payment and file delivery and has become a common tool for small “indie makers” and one-person businesses.
Many of these bundles lean on the language of value investing and opportunity. They echo Warren Buffett’s idea that “price is what you pay, value is what you get,” and promise that the knowledge inside is worth many times the cost. Black Friday discounts amplify this framing: for a short time in late November, prices drop while the promise of value stays high. In this setting, “Productize Yourself” means learning to turn skills and knowledge into digital products—books, courses, templates, software—that scale better than selling time by the hour. “Learn Value” means understanding what people truly care about, what problems hurt enough to pay for, and how to design offers around those pains.
Black Friday itself begins as a practical historical accident. Police in Philadelphia use the term in the 1960s to describe the traffic and crowds that flood the city after Thanksgiving. Retailers later prefer a more positive story, saying that this day marks the shift from losses (“in the red”) to profit (“in the black”). Over time, the name spreads across the United States and then to many other countries, and finally to online sales on platforms like Gumroad.
Classic roots: from caves and idols to value and conflict
The deeper content behind these products comes from a long line of thinkers.
Plato’s allegory of the cave shows prisoners chained so they see only shadows on a wall, which they mistake for reality. One prisoner escapes, struggles with the light, and finally sees the sun and the real world. When he returns, most people do not want to listen. This story becomes a model for education, media, and illusion: people live among shadows and resist the painful work of turning around.
Aristotle’s Nicomachean Ethics describes virtue as a habit that usually lies between two extremes: courage between cowardice and rashness, generosity between stinginess and waste. It teaches that the best life comes from repeated, balanced choices. The word “Nicomachean” refers to his son or father, both named Nicomachus, to whom the work is tied.
Francis Bacon warns about “idols of the mind,” stable patterns of error that distort thinking. Some idols come from human nature, some from personal temperament, some from language, and some from blind loyalty to old systems. The model is clear: good thinking requires active defence against these inner idols.
René Descartes offers the famous “cogito”: when everything is doubted, the act of doubting still proves that a doubter exists. “I think, therefore I am” becomes a mental model of radical starting points and of the search for certainty.
Friedrich Nietzsche speaks of “transvaluation of values” and the “overman” or “superman.” The first idea challenges the inherited moral code of a culture and asks whether values should be turned upside down. The second presents an ideal human who creates personal values, embraces life fully, and lives beyond resentment. This becomes a model for questioning norms and for seeing how values change across time.
Edward Gibbon’s multi-volume The History of the Decline and Fall of the Roman Empire shows how civilisations decay. Rome does not fall in a single shock. It weakens through internal conflict, political corruption, loss of civic virtue, financial strain, and military overreach. The model is slow decline: systems can look strong from the outside while their internal glue dissolves.
In social thought, W. E. B. Du Bois writes about “double consciousness”: the painful feeling of seeing oneself both through one’s own eyes and through the eyes of a dominant, often hostile, society. The reality of conflict appears not only between groups, but inside individuals who must carry two perspectives at once.
Economics adds the mental model of aggregate demand, the total planned spending in an economy. In a crisis, many people and firms cut spending and investment at the same time, which pushes the whole system down further even when physical capacity remains. This framework explains why some crises feed on themselves and why support to demand can stabilise a system.
Albert Einstein’s theory of relativity gives a deep model of space, time, and gravity. Space and time merge into one fabric—spacetime—that bends around mass and energy, and gravity appears as this curvature. Time and length are no longer absolute but depend on the observer’s motion and position. For thinking, this suggests a powerful idea: many things that seem fixed are frame-dependent.
Modern curators: Farnam Street, LessWrong, and The Latticework
In the present, several projects gather and organise mental models for busy readers.
Farnam Street, founded by Shane Parrish, focuses on “mastering the best of what other people have already figured out.” The site FS.blog and the book series The Great Mental Models present tools from physics, biology, psychology, economics, and more. Parrish has a background as a cybersecurity specialist at Canada’s intelligence services and later builds a career around clear thinking, timeless principles, and decision-making.
LessWrong is an online community focused on rationality. Many core essays explain Bayesian thinking: beliefs as probabilities, updated with new evidence using Bayes’s theorem. The site hosts discussions of decision theory, artificial intelligence, cognitive biases, and ways to align everyday reasoning with the mathematics of uncertainty.
Blas Moros builds a large library of book summaries, essays, and an “idea portfolio” at his site The Rabbit Hole. Out of this work comes The Latticework, a curated membership platform that interconnects hundreds of mental models from many disciplines in a guided way. Interviews with Moros describe his background as a high-level tennis player, his deliberate reading of hundreds of books, and his focus on multi-disciplinary thinking and compounding learning over time.
These projects share a vision: take “big ideas from the big disciplines,” explain them clearly, and help people tie them together into a mental lattice that makes the world feel more understandable.
Naval Ravikant and playing long games with compounding
Naval Ravikant provides a living example of playing long games in technology, investing, and thinking. He is born on 5 November 1974 in New Delhi, later moves to New York, attends Stuyvesant High School, and graduates from Dartmouth College with degrees in Computer Science and Economics.
He co-founds Epinions in 1999, a consumer review site that later merges into Shopping.com. He runs an early-stage fund called The Hit Forge, invests in companies such as Twitter, Uber, Stack Overflow, Postmates, and Yammer, and later co-founds AngelList, a platform that connects startups, angel investors, and job-seekers and helps change how early-stage funding works. He also co-founds the crypto fund MetaStable Capital.
Ravikant often speaks about leverage, specific knowledge, and long-term games. Leverage appears as capital, code, media, or teams that let one person’s decisions scale far beyond personal effort. “Play long-term games with long-term people” becomes one of his main ideas: relationships, reputation, and knowledge compound over decades in the same way that capital compounds in value investing.
This picture fits well with antifragility. A person can see a career not as one job but as many small bets: building skills, trying projects, shipping digital products, investing in social capital, and learning from each outcome.
Indie makers, SaaS, MVPs, and building in public
In the new creator and founder economy, many people act as “indie makers.” They build small software-as-a-service (SaaS) tools, newsletters, courses, or communities on the side or as their main work. SaaS means software that runs online and is rented by subscription instead of bought once.
A common pattern is to start with a Minimum Viable Product (MVP): the simplest version that solves a real problem and lets users try it. Marketing pages present a clear Call to Action (CTA): a button or sentence that says “Sign up,” “Start free trial,” or “Download now.” Makers track the Lifetime Value (LTV) of a customer—the total revenue over the relationship—and the Customer Acquisition Cost (CAC)—the cost of winning one new customer. If LTV does not safely exceed CAC, the model is fragile.
Some founders choose to “build in public.” They share revenue numbers, roadmaps, and failures, and they talk openly about what works and what does not. This approach is risky emotionally but acts as a constant feedback loop. It also builds trust with users who see the process rather than only the final result.
In these spaces, synergy means more than “working together.” It means designing systems where one effort strengthens another: a blog that feeds a newsletter, a newsletter that feeds a course, a course that feeds a software product, and each piece supports the others.
Thinking under uncertainty: second-order effects and simple tools
Decision-making under uncertainty benefits from several simple models.
Second-order thinking asks what happens after the first obvious step. A decision can bring direct effects and later effects. For example, large discounts may bring a wave of customers now but train them to wait for sales later. Second-order thinking forces a person to ask, “And then what?”
Heuristics are mental shortcuts. They help when time and information are limited, but they also create traps. People rely on availability (judging risk by how easy examples come to mind), anchoring (sticking too closely to the first number or idea seen), and confirmation (looking only for evidence that supports a current belief). Good meta-thinking means stepping back to ask, “What is my brain doing here? Which shortcut is active? Does it fit this situation?”
Several tools help reduce risk in projects:
- A pre-mortem imagines that a project has already failed and asks what went wrong, so hidden risks show up earlier.
- The OODA loop—observe, orient, decide, act—comes from military strategy and applies to business and life; the key is to update orientation with each loop instead of defending the original picture.
- Skin in the game says that decision-makers should share in the upside and downside of outcomes, making them more careful and honest.
- Via negativa suggests improving things first by removing what is clearly harmful or unnecessary instead of adding more layers.
These tools combine well with growth mindset and Stoic practice. Growth mindset sees abilities as improvable with effort and feedback. Stoicism teaches attention to what can be controlled, acceptance of what cannot, and a focus on inner character rather than external swings. Memento mori—remember that life ends—encourages better use of time, while amor fati—love of fate—invites a person to treat obstacles as material for growth.
Robert Cialdini’s work on persuasion identifies levers that reliably move decisions: reciprocity, commitment and consistency, social proof, liking, authority, scarcity, and a sense of unity. Knowing these levers allows a person to persuade more ethically and also to recognise when others try to push too hard.
Dale Carnegie’s advice on human relations and Stephen Covey’s “seven habits” give simple social skills: listen more than you speak, avoid needless criticism, focus on what is important but not urgent, think win-win, and try to understand the other side before asking to be understood. These habits are practical mental models for daily conversation and cooperation.
Stories, fourth walls, gimmicks, and the feel of culture
Mental models also appear in stories and media tricks.
The “fourth wall” is the invisible barrier between actors and audience. The other three “walls” are the back and sides of the stage or set; the fourth is the imaginary front. When a character talks directly to the viewer, the wall breaks. In some comedies and dramas, this becomes a powerful way to show inner thoughts and to comment on the action. In one modern British series about a young woman in London, direct asides to the camera start as jokes but slowly reveal distance and fear of intimacy: the character hides behind humour instead of fully entering her own life.
A gimmick is a clever device that risks being shallow if used only for shock or style. Breaking the fourth wall, flashbacks, or unusual narrative structures can all be gimmicks if they do not serve the story. When they connect deeply to theme and character, they become strong artistic tools.
Even the phrase “devil’s advocate” is a mental model. It points to a person who takes the opposite side on purpose, not because of personal belief, but to test an argument and uncover weak points. Used well, this habit makes decisions more robust.
Language, Dutch verbs, and everyday misunderstandings
Language carries mental models quietly.
Take a simple warning: “Do not lose the key.” In Dutch this can be “Verlies de sleutel niet” or “Raak de sleutel niet kwijt.” The structure places the verb first, then the object, then the negation. It is a clear instruction about future behaviour.
A natural promise in reply is “Ik zal het niet doen,” which means “I will not do it,” or “Ik zal het niet vergeten,” “I will not forget it.” The helper verb “zal” marks a future-oriented promise.
The sentence “Ik wil niet” means “I do not want to.” It is grammatically correct but communicates something else. Instead of accepting the request, it signals lack of desire to act. The difference is small in words and large in social meaning.
Dutch also often uses the present for future events when a time word is added (“Morgen werk ik thuis,” “Tomorrow I work at home”) and uses “gaan” with an infinitive for near plans (“Ik ga koken,” “I am going to cook”). Many verbs split in main clauses, as in “Ik bel je morgen op” where the small particle “op” moves to the end. Learning these patterns is not only grammar work; it is building mental models for how Dutch speakers organise time, action, and politeness.
Cultural style adds another layer. A quiet colleague who rarely shows strong emotion can look bored or distant to someone from a more demonstrative culture. A better internal model is more generous: silence can mean careful attention, social caution, or simple tiredness. Asking open questions and giving space for their contributions helps reveal what their style really means.
Learning to argue well
Clear thinking often begins with clear argument.
CrashCourse’s philosophy series, produced with PBS Digital Studios, includes a short video titled “How to Argue – Philosophical Reasoning: Crash Course Philosophy #2.” It explains the structure of arguments—premises and conclusions—what it means for an argument to be valid or invalid, and how formal reasoning can still lead to false conclusions if the premises are wrong. It shows common patterns of fallacy and gives a basic toolkit for judging arguments in everyday life.
Media like this fit neatly into the larger picture of mental models. They translate abstract ideas about logic into simple, visual lessons that anyone with an internet connection can watch.
Conclusions
A slow lattice, not a quick download
Better thinking does not arrive as a single book, course, or Black Friday bundle. It grows slowly as a lattice of ideas.
Classic works offer stories and concepts: prisoners in a cave, virtues between extremes, idols of the mind, collapsing empires, economic cycles, and deep theories of spacetime. Modern projects curate and connect these ideas for busy readers. Digital products package them in neat formats—checklists, maps, cards, and memos. Investors, writers, and makers show how these models guide choices about money, work, and learning.
The real change happens when these models become part of daily attention. A person sees a persuasive message and quietly checks which levers it uses. They plan a project and run a pre-mortem. They notice a feeling of certainty and ask which heuristic or bias might be active. They look at a tense meeting and remember that most people’s quirks sit on top of ordinary needs: safety, respect, space, and understanding.
Language and culture reinforce the lesson. A tiny gap between “I will not” and “I do not want to” in Dutch, or a glance to camera from a character on screen, reveals how much meaning depends on subtle shared models.
Over time, this practice compounds like interest. The world does not become simple, but it becomes more legible. Conflicts feel less like pure chaos and more like the meeting of different maps. The mind gains a clearer sense of what is known, what is uncertain, and what can never be fully controlled.
In that space, mental models cease to be a fashion and become something quieter and more useful: a way to move through complexity with a little more clarity and a little more kindness.
Selected References
[1] Farnam Street – “Mental Models: The Best Way to Make Intelligent Decisions,” FS.blog. https://fs.blog/mental-models/
[2] Farnam Street – “The Great Mental Models” project description. https://fs.blog/tgmm/
[3] LessWrong – “Bayesianism” and “What is Bayesianism?” https://www.lesswrong.com/w/bayesianism and https://www.lesswrong.com/posts/AN2cBr6xKWCB8dRQG/what-is-bayesianism
[4] CrashCourse Philosophy – “How to Argue – Philosophical Reasoning: Crash Course Philosophy #2.” https://www.youtube.com/watch?v=NKEhdsnKKHs
[5] Black Friday history – Encyclopaedia Britannica and Wikipedia entries on “Black Friday (shopping).” https://www.britannica.com/story/why-is-it-called-black-friday and https://en.wikipedia.org/wiki/Black_Friday_(shopping)
[6] Gumroad – platform overview. https://gumroad.com and Wikipedia article “Gumroad.”
[7] Naval Ravikant biography – Wikipedia and related investor profiles. https://en.wikipedia.org/wiki/Naval_Ravikant and https://www.evalyze.ai/investors/naval-ravikant
[8] Shane Parrish and Farnam Street – article on his background and role as a curator of mental models. https://www.wral.com/story/how-an-intelligence-expert-helps-wall-street-mavens-think-smarter/17987254/ and https://www.allamericanspeakers.com/celebritytalentbios/Shane%2BParrish/450862
[9] The Rabbit Hole and The Latticework – Blas Moros’s site and about pages. https://blas.com/ and https://ltcwrk.com/about/
[10] Plato’s allegory of the cave – Wikipedia entry. https://en.wikipedia.org/wiki/Allegory_of_the_cave
[11] Background on Aristotle, Bacon, Descartes, Nietzsche, Du Bois, Gibbon, and Einstein – standard philosophy and science references such as Encyclopaedia Britannica.
[12] Robert Cialdini – “Seven Principles of Persuasion” and related material on influence. https://www.influenceatwork.com/7-principles-of-persuasion/
Appendix
Aggregate demand
Aggregate demand is the total planned spending on goods and services in an economy at a given time, combining consumption, investment, government spending, and net exports, and it helps explain booms and recessions.
Allegory of the cave
The allegory of the cave is a story from Plato about prisoners who see only shadows on a wall and believe them to be reality until one escapes and discovers the world outside, creating a model for ignorance, education, and resistance to new truths.
Angel investing and venture capital
Angel investing and venture capital describe funding for young companies: angels invest personal money at very early stages, while venture capital firms invest pooled money with the aim of high growth and potential large returns in the future.
Antifragility
Antifragility is a property of systems that become stronger after shocks, stress, or volatility, as described by Nassim Nicholas Taleb, which encourages designs that gain from small failures instead of breaking.
Black Friday
Black Friday is the Friday after Thanksgiving in the United States, known as a major shopping day with heavy discounts, later adopted worldwide both in stores and online, and its name links to traffic chaos in Philadelphia and to the jump from losses to profit in retail accounts.
Build in public
Build in public is a way of creating products or companies in which founders share progress, revenue, and lessons openly with an online audience, using transparency as both a marketing and learning tool.
Call to Action (CTA)
A Call to Action is a clear instruction in text or design that tells the reader exactly what to do next, such as “Sign up,” “Start free trial,” or “Download now,” and it is central to many product and marketing pages.
Devil’s advocate
A devil’s advocate is someone who takes an opposing view on purpose, not out of personal conviction, in order to test arguments, reveal weak points, and prevent group decisions from becoming too confident.
Dutch future forms
Dutch often expresses the future using the present tense with a time word (“Tomorrow I work at home”), the verb “gaan” plus an infinitive for near plans, and “zullen” plus an infinitive for promises, while word order and small particles at the end of sentences shape tone and meaning.
Fleabag and the fourth wall
The modern British series Fleabag uses direct address to the camera to break the fourth wall, turning the viewer into a confidant and using this device not only as a joke but as a way to show the main character’s emotional distance and discomfort with real intimacy.
Gumroad
Gumroad is an online service that lets creators sell digital products such as ebooks, audio files, courses, and software directly to customers by handling payments, downloads, and simple storefronts.
Heuristics
Heuristics are mental shortcuts or rules of thumb that allow quick judgments with limited information, such as judging risk by recent vivid examples, but they can also lead to systematic errors if not checked.
Indie makers
Indie makers are independent creators who build their own small products—often software, newsletters, or courses—without large teams or investors, relying instead on simple tools, direct customer relationships, and often a “build in public” style.
Latticework
Latticework here refers to a structured network of mental models that support one another, a metaphor drawn from Charlie Munger and used as the name of Blas Moros’s learning platform, which aims to connect ideas from many disciplines.
Learn Value (course idea)
Learn Value describes an educational product theme that teaches people to understand what customers truly care about, how value differs from price, and how to design offers and decisions based on long-term usefulness rather than short-term impressions.
Mental model
A mental model is a simple, useful way to understand a part of the world, such as supply and demand, feedback loops, or confirmation bias, and combining many models from different fields leads to better understanding and decisions.
Meta-thinking
Meta-thinking is thinking about thinking itself, such as noticing when a bias or heuristic might be active, reflecting on how decisions are made, and adjusting the process rather than only the specific choice.
Minimum Viable Product (MVP)
A Minimum Viable Product is the simplest version of a product that still solves a real problem, released to test interest and gather user feedback before more features and investments are added.
Monomyth
The monomyth, or hero’s journey, is a pattern described by Joseph Campbell in which a hero receives a call to adventure, leaves the familiar world, faces trials, reaches a crisis, gains new insight or power, and returns to share it with others.
Memento mori and amor fati
Memento mori is a Stoic reminder that life is finite and death is certain, encouraging focus on what matters, while amor fati is the attitude of loving one’s fate and treating obstacles as material for growth rather than only as misfortune.
OODA loop
The OODA loop is a four-step cycle—observe, orient, decide, act—developed by strategist John Boyd to describe effective behaviour in fast-changing situations, where quick and accurate loops can give an advantage.
Productize yourself
To productize yourself is to turn personal skills, insights, or experience into scalable products—like books, courses, or software—so that income no longer depends only on hours worked but on the value created for many people.
Second-order thinking
Second-order thinking is the habit of asking about later consequences of an action, not only the first obvious result, and it helps avoid choices that feel good now but create problems over time.
Skin in the game
Skin in the game is the condition in which decision-makers share in both the benefits and the harms of their choices, making them more likely to act carefully and align their interests with others.
Stoic practice
Stoic practice is a set of exercises based on ancient Stoic philosophy; it focuses on controlling one’s own judgments and actions, accepting what cannot be controlled, and living with courage, justice, moderation, and wisdom.
Synergy
Synergy is the effect that occurs when different parts of a system work together in a way that produces a result greater than the simple sum of their individual effects, such as content, community, and product each amplifying the others.
Think Better (course or book theme)
Think Better describes a product theme that promises to teach additional mental models, frameworks, and habits that make reasoning clearer and more effective in everyday life and in complex decisions.
Value investing
Value investing is an investment approach associated with Benjamin Graham and Warren Buffett that focuses on buying securities for less than their estimated intrinsic value and holding them long term while the true value is realised.
My Diary - Leonardo Cardillo 