What [software] must not do is not the inverse of what it…
![“What [software] must not do is not the inverse of what it must do. .” quote by Nancy Leveson](https://sms4smile.com/q/img-quotes/cf5/nancy-leveson-56176_inverse_what-software-must-not-do-is-not-the-inv_1537245.jpg)
“What [software] must not do is not the inverse of what it must do. .”
About This Quote
This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation.
Software should focus on achieving its intended functions, not merely avoiding errors; the opposite goal is insufficient.
In simple terms: Software must do what it should, not just avoid mistakes.
Key Takeaway
Design systems that fulfill core purposes robustly.
Themes
engineering
software
safety
design
Mood
analytical
pragmatic
Type
technical
instructional
When to use this quote
- critical infrastructure
- medical devices
- autonomous vehicles
Key Concepts
goal‑oriented design
failure prevention
system integrity
Questions to Reflect On
- What primary functions should the software prioritize?
- How can we test for both success and failure modes?
A Different Perspective
Avoiding errors alone doesn’t guarantee safety.