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• Economic Moats — What Lets a Company Survive for Decades

  A look at what an economic moat is and why it matters for long-term investing. We cover the five types of moats, the risk of erosion, how to gauge a moat with ROIC, and how the idea connects to value investing.

  2026-06-18 · 23 min read #finance#investing#economic-moat#value-investing#competitive-advantage

• Reading Earnings Season — The Language of Results and Guidance

  How to read the earnings season that returns every quarter. We cover the structure of an earnings release, consensus and surprise, why guidance moves stocks, reading the conference call, the trap of non-GAAP metrics, and

  2026-06-18 · 22 min read #finance#investing#earnings-season#guidance#eps

• China and Emerging Markets 2026 — Between Risk and Opportunity

  A look at China and emerging markets in 2026 through the lenses of economy and policy, real estate, technology self-reliance and regulation, geopolitics and de-risking. We weigh alternative markets such as India, a diver

  2026-06-18 · 20 min read #china-stock#emerging-markets#india#geopolitics#diversification

• Korea Stock Market 2026 Outlook — Semiconductors, Value-Up, and the Challenges Ahead

  We examine the Korean stock market in 2026 through four axes: semiconductor weighting, the Value-Up program, foreign investor flows and the exchange rate, and governance reform. We weigh the bull and bear cases in a bala

  2026-06-18 · 24 min read #korea-stock#kospi#semiconductor#value-up#investing

• The June 2026 AI Rally Rollercoaster — Anatomy of the Semiconductor Selloff and Rebound

  A data-driven walkthrough of the early June 2026 semiconductor selloff and its rapid rebound. We examine the drivers of volatility through valuation, earnings, and interest rates, and weigh the bull and bear cases alongs

  2026-06-18 · 10 min read #finance#ai-rally#semiconductors#volatility#nvidia

• In the End You Need Your Own Story — Learning That Applies to Life

  No matter how much you learn, it rings hollow until you make it your own. Even when you use AI, the learning only counts if it applies to your life. This essay is about restating learning in your own words, objectifying

  2026-06-17 · 21 min read #learning#metacognition#storytelling#ai#authenticity

• Output Practice — Raise Output per Hour, Raise Quality per Output

  Escape the trap of piling up input and adopt the view that output builds skill. This essay covers the axis of raising output per hour and the axis of raising quality per output, speaking practice in English and Japanese,

  2026-06-17 · 15 min read #output#practice#language-learning#storytelling#feedback

• Journaling for Clarity — Recording Myself in Korean, English, and Japanese

  A journal is the cheapest tool there is for organizing thought and separating emotion. I sort out my mind in Korean, then write in English and Japanese too, practicing language output at the same time. Here is the two-bi

  2026-06-17 · 23 min read #journaling#self-improvement#language-learning#reflection#habit

• Controlling Body, Thought, and Speech — The Three Channels We Use to Meet the World

  I only started playing table tennis well after I learned to control my body. Speaking a language well turned out to be the same thing: controlling my thoughts and moving my mouth and muscles precisely. Starting from a no

  2026-06-17 · 23 min read #self-improvement#meta-cognition#self-regulation#habit#mindset

• Manage Yourself Like an Athlete — Your Body Is the Fundamentals

  The best knowledge workers manage their bodies the way athletes do. This essay covers posture and circulation, a steady sleep-nutrition-exercise routine, treating recovery as training, and the quiet value of a hobby spor

  2026-06-17 · 18 min read #self-management#health#routine#recovery#productivity

• Learn From the Masters, Push Yourself — A Growth Method for the Animal That Adapts

  Human beings are animals that adapt. Play only against weaker opponents and your skill quietly plateaus. This essay is about learning from people better than you, stepping just outside your comfort zone, rewarding yourse

  2026-06-17 · 23 min read #growth#learning#mindset#deliberate-practice#mentorship

• Divide and Conquer, No Procrastination — You Can Do It All

  Big tasks feel overwhelming, so we keep putting them off. But broken into small pieces, you actually can do it all. This is about divide and conquer, the two-minute rule, momentum, and tracking systems to finish without

  2026-06-17 · 23 min read #productivity#procrastination#focus#mindset#habits

• Trust the System, Not Yourself — The Secret to Not Making Mistakes

  Human memory and willpower are far more fragile than we like to admit. What prevents mistakes is not stronger willpower but a well-designed system. This is about building structures of checklists, automation, and externa

  2026-06-17 · 23 min read #system#checklist#automation#productivity#mindset

• Metacognition and Strengthening the Circuit — Retrieval Builds the Brain

  Listening alone does not build the circuit. Only when you retrieve does the circuit fire and grow stronger. This essay covers the science of retrieval practice, using metacognition to discover what you do not know, and m

  2026-06-17 · 17 min read #metacognition#retrieval-practice#learning#language#memory

• When Times Are Hard, Imagine the Worst and Separate Your Emotions

  The Stoics deliberately trained negative visualization — picturing the worst in advance. Imagining a deeper bottom when times are hard lets you endure the present, and separating emotion from fact reduces the wobble. But

  2026-06-17 · 20 min read #stoicism#resilience#emotional-regulation#self-improvement#mindset

• FingerScore Hardware 3 — MCU Firmware and Gesture Input Processing

  This post covers the brain of the FingerScore BLE ring device for racket-sports score keeping: the MCU firmware. From the structure of init, main loop, interrupts, and low-power sleep, through detecting buttons and gestu

  2026-06-17 · 17 min read #fingerscore#firmware#mcu#embedded#gesture

• FingerScore Hardware 4 — Designing BLE Wireless Communication (From GATT to Mobile Integration)

  We design the BLE wireless communication at the heart of the FingerScore smart-scoring ring from the ground up. GAP/GATT concepts, a custom score service, pairing security, Web Bluetooth and Android integration, power sa

  2026-06-17 · 15 min read #fingerscore#ble#bluetooth#gatt#embedded

• FingerScore Hardware 6 — PCB Design and Miniaturization (Building It Into a Ring)

  We cover the final step that turns the FingerScore circuit into a real, touchable ring: PCB design. The schematic-to-PCB flow, component placement and routing, ring form-factor constraints, 2.4GHz antenna layout, DFM and

  2026-06-17 · 15 min read #fingerscore#pcb#kicad#antenna#miniaturization

• FingerScore Hardware 2 — Electronics Fundamentals (From Voltage, Current, and Resistance to Digital Signals)

  Everything you need from electronics fundamentals to build the FingerScore ring device, in one piece. We walk through Ohm law and voltage dividers, pull-up and pull-down resistors, capacitors, LED current-limiting calcul

  2026-06-17 · 23 min read #fingerscore#electronics#hardware#gpio#i2c

• FingerScore Hardware 5 — Power, Battery, and Circuit Design

  We cover, from scratch, the power design that actually keeps the FingerScore ring on. A power budget calculation, coin cell vs. LiPo, charging ICs and protection circuits, LDOs and buck converters, decoupling, low-power

  2026-06-17 · 16 min read #fingerscore#power#battery#lipo#circuit