It is clear, you need some bases to be able to reasonice and understand the cause of an problem. You can find the cause of an problem why an engine don't work with some basic knowledge about physics, but even an intelligent aborigen who has no knowledge about mecanics and physic never can, also not a person which only had memorized data without understandig it, can't But the current education system priorice the latter, because of this there are a lot of integral idiots with graduation, which outside of their routine don't understand anything.