100 curated investment principles from Buffett, Munger, Graham, Lynch & more — ready to use in your code.

Curated by KeepRule.com — the investment principles encyclopedia.

npm install keeprule

const keeprule = require('keeprule');

// Get a random principle
const principle = keeprule.getRandom();
console.log(`"${principle.text}" — ${principle.author}`);

// Get all principles by Warren Buffett
const buffett = keeprule.getByAuthor('Buffett');
console.log(`${buffett.length} principles from Buffett`);

// Search for "margin of safety"
const results = keeprule.search('margin of safety');
results.forEach(r => console.log(r.text));

Returns a random investment principle.

const p = keeprule.getRandom();
// {
//   id: 3,
//   text: "Price is what you pay. Value is what you get.",
//   author: "Warren Buffett",
//   category: "Value Investing",
//   source: "Berkshire Hathaway Shareholder Letter, 2008"
// }

Returns multiple random non-repeating principles.

const principles = keeprule.getRandomMultiple(5);
// Returns 5 random principles

Filter principles by author name (case-insensitive partial match).

keeprule.getByAuthor('Munger');    // All Charlie Munger principles
keeprule.getByAuthor('Graham');    // All Benjamin Graham principles
keeprule.getByAuthor('Lynch');     // All Peter Lynch principles

Filter principles by category (case-insensitive partial match).

keeprule.getByCategory('Risk Management');
keeprule.getByCategory('Value Investing');
keeprule.getByCategory('Mental Models');

Full-text search across text, author, category, and source.

keeprule.search('compound');       // Principles mentioning compound interest
keeprule.search('fear');           // Principles about fear/greed
keeprule.search('intelligent');    // The Intelligent Investor references

Returns all 100 principles.

const all = keeprule.getAll();
console.log(`Total: ${all.length} principles`);

Returns a sorted list of all unique author names.

keeprule.getAuthors();
// ["Albert Einstein", "Alexander Elder", "Benjamin Graham", "Charlie Munger", ...]

Returns a sorted list of all unique categories.

keeprule.getCategories();
// ["Behavioral Finance", "Business Quality", "Circle of Competence", ...]

Get a specific principle by its ID (1-100).

const p = keeprule.getById(1);
// Rule No. 1: Never lose money...

Returns the total number of principles.

keeprule.count(); // 100

Each principle object has:

• Value Investing — Core value investing principles
• Risk Management — Managing and understanding risk
• Market Psychology — Understanding market behavior
• Long-term Investing — Patience and compound growth
• Mental Models — Thinking frameworks
• Behavioral Finance — Psychology of investing
• Circle of Competence — Knowing your limits
• Decision Making — Better investment decisions
• Business Quality — Evaluating businesses
• Financial Discipline — Spending, saving, discipline
• Portfolio Management — Diversification and allocation
• Research — Due diligence and analysis

• Warren Buffett — The Oracle of Omaha
• Charlie Munger — Berkshire Hathaway Vice Chairman
• Benjamin Graham — Father of Value Investing
• Peter Lynch — Legendary Fidelity fund manager
• John Templeton — Global investing pioneer
• John Bogle — Vanguard founder, index fund advocate
• Jesse Livermore — Legendary stock trader
• Philip Fisher — Growth investing pioneer
• George Soros — Quantum Fund founder

• Daily principle bot — Display a random principle every day
• Financial apps — Enrich your app with curated wisdom
• CLI tools — Show investing tips in terminal
• Education — Teach investment principles programmatically
• Screensavers / wallpapers — Dynamic investing quotes

Full TypeScript definitions are included:

import { getRandom, getByAuthor, Principle } from 'keeprule';

const p: Principle = getRandom();
const buffett: Principle[] = getByAuthor('Buffett');

Visit KeepRule.com for:

• Interactive investment principle scenarios
• Deep-dive explanations with real-world examples
• AI-powered investment principle analysis
• Community discussions and notes

MIT - see LICENSE

Issues and PRs welcome at GitHub.

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