If you can't logically reason about programs written in a language, how is it ever a good choice to use? You can never perfectly logically reason about any pro

If you can't logically reason about programs written in a language, how is it ever a good choice to use? You can never perfectly logically reason about any program – your ability to reason about a given program varies on a scale of 'easy to reason about' to 'difficult to reason about'. While it's not always the case, it's easy to see that in some situations the cost of making a language easier to reason about can outweigh the benefits. The 'goodness' or otherwise of a language must factor in the difficult of reasoning about it, but that itself is not a sufficient condition to describe its quality.