“To remain in ignorance of the enemy's condition simply because one grudges the outlay of a hundred ounces of silver is the height of inhumanity.”
Refusing to pay for knowledge that would save lives is a moral failure, not thrift; buy the information.
Chapter 13 makes its moral claim early: to remain in ignorance of the enemy’s condition simply because one grudges the outlay of a hundred ounces of silver is the height of inhumanity. Inhumanity — not error, not thrift, but cruelty. Sun Tzu frames under-buying intelligence as a harm to the people who pay for its absence: the soldiers marched blind, the teams staffed for a war the spreadsheet could have prevented.
A firm declines a $30K market study — real money, visibly, from a real budget — and instead launches $4M of product into the segment the study would have flagged as consolidating. Twelve people are laid off in the aftermath. The refusal looked like prudence in the budget meeting and was, in the verse’s vocabulary, inhumanity: the savings were booked by one group, the costs paid by another. Grudging the ounces and spending the army is not a trade — it is an accounting trick with casualties.
Generosity toward intelligence is not gullibility toward information sellers — the chapter immediately follows with how spies are managed, judged, and cross-checked, and Chapter 9’s dust-reading keeps the analytic discipline intact. What is condemned is refusing to fund knowing at all. Buy the knowledge, then interrogate it; never skip the buying and call the skip savings.