I think that this is a fundamental issue on this thread - emotion vs. rationality.
I don't know if that is true. For instance, if someone I work with came to me with a question, say "Hey Viv, take a look at this configuration for a computing system and the projected workload. Will this system meet the workload requirements?", I would then do some math. There are almost always things we don't know, things we can't plan or calculate for in exercises like this, so you have to used past experience, educated guesses, etc.. If, after looking at everything, compiling what we do know with the things we had to makes assumptions or best guesses for and doing the math, etc., would it be an emotional belief to say "I believe this design will be adequate"?