I just don't believe it's possible to reason without consciousness. Combined with intelligence, memory, etc it leads to actual understanding rather than just imitation, which is where AI is today.
This is called an argument. It's what philosophers make.
Your attitude is a pretty typical one: "Philosophy is stupid, but this philosophical viewpoint that I have is special and somehow not bound to the things that apply to philosophy." It's a very common and predictable move from those that lack knowledge of the subject; the New Atheists and the philosophy of religion are a very prominent example.
Is it possible to compute without consciousness? (Yes.)
Is it possible to perform calculation over ideas without consciousness? Apparently so.
> understanding
You should prove that a "formal" form of understanding would be insufficient for reasoning.