On the other hand, the liberal use of the term “science” (even engineering as in computing engineering), makes our Physics friends flinch at our day-to-day methodology. We don’t calculate programs. We don’t derive implementations. And when something goes wrong, our assessment method is so empirical that it would be equivalent to building a copy of the failed bridge, and observe bolt by bolt – with intuition (and stack dumps) guiding which bolts to observe first – hoping to find the one that fails. This arguable “lack of scientific rigour” is well reflected when Donald Knuth wrote one of the most rigorous treatises on computer science, and decided to call it “The Art of Computer Programming”.