With regards to definitive benefit that&#x27;s backed up by scientific study (rather than just anecdote)-- the UK&#x27;s Ministry of Defense commissioned a study (IV&amp;V) on the error rate of long-lived code comparing C code bases (static but not too strict) vs Ada (static and fairly strict). They presented their findings Ada-Europe 2001. There was about a 1 to 10 error ratio. They subset the Ada code into formally verified by SPARK code, and the error rate -- I kid you not -- dropped another order of magnitude. I&#x27;d assert based on that study static typing is definitively more reliable when your problem domain is set in stone [the operational semantics of flight, stock markets, power plants]. Of course that doesn&#x27;t extend to any &#x27;exploratory&#x27; computing where your domain isn&#x27;t strictly (pardon the pun) defined.<p>RE: Parametric polymorphism being &quot;useful&quot; - a pedant like me would claim for it to be of use, one has to demonstrate one clear instance of PP being of use - trivial or not - after which PP gains the attribute &quot;useful&quot; ;)