India, Oct. 3 -- Engineers rarely speak of wisdom. They speak of loads, stresses, tolerances, margins and safety factors. Yet hidden inside one of engineering's most practical numbers is a philosophical idea: safety begins with admitting that we do not know everything.

A safety factor is a numerical expression of humility. A bridge may be designed to carry a certain load, but the engineer does not assume that every calculation, material property, construction detail or future circumstance will behave exactly as predicted. Instead, the structure is given additional capacity. If a column is expected to carry a particular load, it is designed to withstand more. The excess is not waste. It is an acknowledgement of uncertainty.

This principl...