Rebuilding economic intuition from the ground up.https://penluma.com/https://penluma.com/blog/economics-from-first-principles/00-index-learn-economics/https://penluma.com/blog/economics-from-first-principles/00-index-learn-economics/A from-scratch economics course for beginners. No jargon, no prior knowledge - just 32 plain-English guides that rebuild how the economy really works.Sat, 04 Jul 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/01-what-economics-is-and-why-it-exists/https://penluma.com/blog/economics-from-first-principles/01-what-economics-is-and-why-it-exists/Economics isn't really about money. It's about how people choose when they can't have everything. Here's the one idea that makes the whole field click.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/02-how-economists-think-incentives-margins-and-models/https://penluma.com/blog/economics-from-first-principles/02-how-economists-think-incentives-margins-and-models/Learn how economists think using incentives, thinking at the margin, and simple models. A clear guide to the mental moves that explain everyday choices.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/03-supply-demand-and-how-prices-are-determined/https://penluma.com/blog/economics-from-first-principles/03-supply-demand-and-how-prices-are-determined/Nobody decides what your coffee costs, yet the price is never random. Here is how supply and demand quietly set prices for everything you buy.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/04-markets-competition-and-when-markets-fail/https://penluma.com/blog/economics-from-first-principles/04-markets-competition-and-when-markets-fail/Markets usually serve us well, but four classic market failures break them. Learn how monopolies, externalities, public goods, and information gaps work.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/05-consumer-behavior-and-how-people-really-decide/https://penluma.com/blog/economics-from-first-principles/05-consumer-behavior-and-how-people-really-decide/Why does cheap water cost nothing while diamonds cost a fortune? Consumer behavior explains how people really decide what to buy, and how sellers use it.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/06-what-money-is-and-why-it-has-value/https://penluma.com/blog/economics-from-first-principles/06-what-money-is-and-why-it-has-value/Why does a slip of paper buy real food and labour? Discover what money actually is, why fiat money has value, and what happens when trust in it breaks.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/07-how-banks-work-and-how-they-create-money/https://penluma.com/blog/economics-from-first-principles/07-how-banks-work-and-how-they-create-money/Banks don't lend out savings like you think. They create money from nothing every time they make a loan. Here's how banks really work, in plain language.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/08-central-banks-and-monetary-policy/https://penluma.com/blog/economics-from-first-principles/08-central-banks-and-monetary-policy/How central banks move one interest rate to steer jobs, prices, mortgages, and the dollar - and why their decisions take a year to land in your life.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/09-loans-credit-debt-and-interest-rates/https://penluma.com/blog/economics-from-first-principles/09-loans-credit-debt-and-interest-rates/Interest rates explained in plain English: why interest exists, how your credit score sets your rate, and why real returns beat the number on your statement.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/10-inflation-deflation-and-the-value-of-money/https://penluma.com/blog/economics-from-first-principles/10-inflation-deflation-and-the-value-of-money/Why does a coffee cost ten times what it did in 1980? This plain-English guide to inflation, deflation, and the value of money explains it without the jargon.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/11-measuring-an-economy-gdp-gnp-cpi-ppp-and-key-indicators/https://penluma.com/blog/economics-from-first-principles/11-measuring-an-economy-gdp-gnp-cpi-ppp-and-key-indicators/GDP, GNP, CPI, and PPP explained in plain language. Learn what each number measures, what it quietly hides, and how to read an economy like a pro.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/12-economic-growth-and-productivity/https://penluma.com/blog/economics-from-first-principles/12-economic-growth-and-productivity/Economic growth and productivity decide why some countries are rich and others poor. Learn the Rule of 70, the Solow model, and why institutions matter most.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/13-wages-labor-markets-and-why-some-jobs-pay-more/https://penluma.com/blog/economics-from-first-principles/13-wages-labor-markets-and-why-some-jobs-pay-more/Why do some jobs pay more than others? It is not effort or virtue. Learn the six forces that set every wage, from skill scarcity to superstar markets.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/14-unemployment-productivity-and-the-labor-force/https://penluma.com/blog/economics-from-first-principles/14-unemployment-productivity-and-the-labor-force/The unemployment rate can fall while no one gets hired. Learn how the rate is really counted, what it hides, and how to read the jobs report like an economist.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/15-the-business-cycle-booms-recessions-and-depressions/https://penluma.com/blog/economics-from-first-principles/15-the-business-cycle-booms-recessions-and-depressions/The business cycle explained in plain language: the four phases, what causes booms and recessions, and the warning signs that a downturn is coming.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/16-fiscal-policy-taxes-spending-deficits-and-national-debt/https://penluma.com/blog/economics-from-first-principles/16-fiscal-policy-taxes-spending-deficits-and-national-debt/Fiscal policy explained simply: how taxes, spending, deficits, and the national debt work, why the debt isn't like your mortgage, and what really limits it.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/17-business-economics-costs-profit-competition-and-pricing/https://penluma.com/blog/economics-from-first-principles/17-business-economics-costs-profit-competition-and-pricing/Why does the same iPhone cost twice as much abroad? This business economics guide shows how costs, margins, pricing, and moats decide which firms win.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/18-how-companies-grow-raise-capital-and-create-value/https://penluma.com/blog/economics-from-first-principles/18-how-companies-grow-raise-capital-and-create-value/Learn how companies create value, raise capital, and grow - from bootstrapping to VC, dilution, and the chain that turns one investment into higher wages.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/19-financial-markets-stocks-bonds-commodities-and-derivatives/https://penluma.com/blog/economics-from-first-principles/19-financial-markets-stocks-bonds-commodities-and-derivatives/Stocks, bonds, commodities, and derivatives explained in plain English: how financial markets price the future, move risk, and reward patience over panic.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/20-real-estate-and-housing-economics/https://penluma.com/blog/economics-from-first-principles/20-real-estate-and-housing-economics/A plain-English guide to housing economics: why house prices rise, how interest rates move them, the real rent-vs-buy math, and what caused the 2008 crash.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/21-international-trade-imports-exports-tariffs-and-agreements/https://penluma.com/blog/economics-from-first-principles/21-international-trade-imports-exports-tariffs-and-agreements/Imports, exports, tariffs, and trade deficits explained in plain language. Learn who really pays a tariff, why trade isn't zero-sum, and what it means for you.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/22-exchange-rates-currency-markets-and-why-currencies-rise-or-fall/https://penluma.com/blog/economics-from-first-principles/22-exchange-rates-currency-markets-and-why-currencies-rise-or-fall/Understand exchange rates in plain language: why currencies rise or fall, how forex markets work, and what moves the value of money across borders.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/23-globalization-and-how-national-economies-are-connected/https://penluma.com/blog/economics-from-first-principles/23-globalization-and-how-national-economies-are-connected/Globalization links national economies through trade, money, people, and ideas. Here is how it works, who wins, who loses, and why it matters to you.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/24-financial-crises-why-they-happen-spread-and-how-economies-recover/https://penluma.com/blog/economics-from-first-principles/24-financial-crises-why-they-happen-spread-and-how-economies-recover/A clear guide to financial crises: why they happen, how panic spreads from one bank to the whole system, and how economies finally recover. No jargon.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/25-inequality-wealth-distribution-and-poverty/https://penluma.com/blog/economics-from-first-principles/25-inequality-wealth-distribution-and-poverty/Understand wealth inequality, why the rich get richer, and how poverty really works. A clear, jargon-free guide to income, wealth, and mobility.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/26-development-economics-why-some-countries-are-rich-and-others-poor/https://penluma.com/blog/economics-from-first-principles/26-development-economics-why-some-countries-are-rich-and-others-poor/Why some countries are rich and others poor is not about smart people or luck. See how institutions, borders, and the rules of the game decide a nation's fate.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/27-technology-automation-ai-and-innovation/https://penluma.com/blog/economics-from-first-principles/27-technology-automation-ai-and-innovation/Will AI take your job? History says automation reinvents work more than it erases it. Here's how technology really drives growth, jobs, and who keeps the gains.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/28-population-demographics-and-the-economy/https://penluma.com/blog/economics-from-first-principles/28-population-demographics-and-the-economy/Why population age and fertility rates quietly decide whether an economy grows or stalls. Demographics in plain language, with real examples you can use.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/29-public-economics-welfare-social-security-and-the-role-of-government/https://penluma.com/blog/economics-from-first-principles/29-public-economics-welfare-social-security-and-the-role-of-government/Public economics explains when government should step in, how it taxes, and why Social Security is at risk, covering market failure, the Laffer curve, and UBI.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/30-environmental-economics-and-sustainable-development/https://penluma.com/blog/economics-from-first-principles/30-environmental-economics-and-sustainable-development/Environmental economics shows pollution is a pricing failure, not just greed. Learn externalities, carbon taxes, the commons, and the social cost of carbon.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/31-behavioral-economics-how-psychology-shapes-the-economy/https://penluma.com/blog/economics-from-first-principles/31-behavioral-economics-how-psychology-shapes-the-economy/Behavioral economics reveals why your brain makes predictable money mistakes - loss aversion, anchoring, nudges, and the biases that drive bubbles and crashes.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principleshttps://penluma.com/blog/economics-from-first-principles/32-how-it-all-connects-ripple-effects-and-the-whole-system/https://penluma.com/blog/economics-from-first-principles/32-how-it-all-connects-ripple-effects-and-the-whole-system/Why does one interest rate decision change your rent, your job, and grocery prices worldwide? Here is how ripple effects move through the whole economy.Mon, 22 Jun 2026 00:00:00 GMTEconomics from First Principles