Normative speech (often using the word "should") means "I have reason to believe". "Reason" usually being based on some a priori[0] knowledge. "we should be ab

Normative speech (often using the word "should") means "I have reason to believe". "Reason" usually being based on some a priori[0] knowledge. "we should be able to do x with y" "y should just work" "users should be able to k" In a problem space such as software, where extreme complexity bordering on chaos is the norm, we we see little evidence supporting common claims of an expected outcome given reason from some fashion of first principles. "Rails should work just fine for this", given some principles about Rails. The problem with the above statement is that you cannot possibly take into account the entire complexity of the final implementation of the appropriate solution beyond the most trivial example. Marsh's first law of software: The complete behavior of any sufficiently useful computer program cannot be reasoned about by a human in polynomial time.[1] Should is a smell. The only should I trust is a passing test. Sorry if that's clear as mud. I've been working to come up with a good explanation for my "normative speech has no place in software" axiom and I'm not sure I've nailed it quite yet. 0: From Wikipedia: A priori knowledge is independent of experience, as with mathematics (3,000 + 2,000 = 5,000), tautologies ("All bachelors are unmarried"), and deduction from pure reason (e.g., ontological proofs). 1: Yes I'm referencing my own made up law. Prove it wrong.