Via Negativa
In theology and philosophy, the focus on what something is not, an indirect definition, deemed less prone to fallacies than via positiva. In action, it is a recipe for what to avoid, what not to do—subtraction, not addition, works better in domains with multiplicative and unpredictable side effects. In medicine, stopping someone from smoking has fewer adverse effects than giving pills and treatments.
Systems learn by removing parts, via negativa.
Applications of via negativa:
Subtractive knowledge
Subtractive prophecy
Via negativa is less likely to have unintended consequences:
Subtraction of a substance not seasoned by our evolutionary history reduces the possibility of Black Swans while leaving one open to improvements. Should the improvements occur, we can be pretty comfortable that they are as free of unseen side effects as one can get.
Another example is on how to navigate life and figure out what you want to do. You may learn more about yourself by trying something and finding out what you don't like. You gain more from failure than success. For example: working a job that you end up not liking informs you of what you don’t like, which better informs your future career decisions.
References
Antifragile by Nassim Nicholas Taleb
Skin in the Game by Nassim Nicholas Taleb