Russell on reality

“We all believe that we live in a common world, peopled not only by sentient beings like ourselves, but also by physical objects. I say we all believe this, in spite of the fact that some philosophers have pretended to doubt it. There are on the one hand solipsists who maintain that they alone exist, and make desperate efforts to make others agree with them. Then there are philosophers who hold that all reality is mental, and that while the feelings we experience when we look at the sun are real, the sun itself is a fiction. And as a development of this view there is the theory of Leibnitz, according to which the world consists of monads that never interact, and perception is in no degree due to the action of the outer world upon the percipient. In this view we may be said to be all dreaming, but the dreams that we all have are identical in structure. These different views, I say, have been advocated by different philosophers, and I do not think that any of them can be disproved. On the other hand, none of them can be proved, and, what is more, none of them can be believed, not even by their advocates.” – Bertrand Russell