How to build a thinking toolbox

1. 01Second-level thinkingAsk "and then what?" three times. The first consequence is obvious; the second and third are where the real cost or payoff usually lives.
2. 02InversionInstead of asking how to succeed, ask what would guarantee failure — then avoid those things. It's often far easier to see.
3. 03Parkinson's lawWork expands to fill the time available. Give a task a deliberately tight box and notice how much of it was padding.
4. 04The Dunning–Kruger trapConfidence peaks early in learning. When you feel certain about something new, treat that as a prompt to go find someone who knows more.
5. 05Opportunity costEvery yes is a no to something unseen. Before committing, name what you're giving up out loud — it makes the trade real.
6. 06Check your model against realityA model is a map, not the terrain. Keep a note of predictions you make and revisit them; models that keep missing should be retired.

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