diff --git a/PRINCIPLES.md b/PRINCIPLES.md
index 8fede39..34b9327 100644
--- a/PRINCIPLES.md
+++ b/PRINCIPLES.md
@@ -36,6 +36,7 @@
 * [Johannes Seitz](https://twitter.com/Ookami86/statuses/515483645663252480) - Software Engineering best practice: Actually understand what you’re doing. Unfortunately it’s rarely used in practice.
 * [Stuart Sierra](https://twitter.com/stuartsierra/statuses/516967544167489536) - "Bugs are dependency-transitive"
 * [Stuart Halloway](https://twitter.com/stuarthalloway/statuses/502906568569286657) - the #1 source of software defects is easy presumtion. Presume nothing.
+* "The Principle of Least Astonishment: Make a user interface as consistent and as predictable as possible"
 
 # from my twitter
 * [MorganGeek](https://twitter.com/MorganGeek/statuses/420907517934178304) - Problem solving / Productivity : Good programmers write code after they found the solution. Un bon programmeur ne commence à coder qu'après avoir trouvé une solution.