In the definition of radical skepticism, it is "the belief that knowledge-most of it at least-cannot be gained" (Coliva, 2021). It is difficult to believe any information without factual evidence, according to most philosophers. Radical skepticism includes statements such as; "if I have hands, then I know I am not an automated brain in a vat. Because I don't know that I am not a handled brain in a vat, I do not know I have hands.". Opinions are very difficult to refute effectively, like most radical skepticism. When faced with even more difficult questions, it is easy to overlook your answer or argument.