First Principles Thinking
First principles thinking means reducing problems to their foundational truths, then building up from there. It's harder than reasoning by analogy but often more powerful.
The Alternative
Most thinking is reasoning by analogy. "X is like Y, so solutions for Y should work for X." This is fast and usually correct. But it fails when X is genuinely different from anything before it.
When First Principles Matters
New territory where analogies mislead. Problems where conventional wisdom has calcified. Situations where "how it's always been done" is clearly not working.
The Process
Identify what you know is true, not what you assume. Ask what's physically possible, not what's been done before. Build solutions from verified truths, questioning each assumption.
The Limitation
First principles thinking is slow and exhausting. Using it for everything is impractical. Save it for decisions that matter enough to warrant the effort.