"Whitehead and Russell ... translate \vdash p imples q into the words 'it is asserted that p implies q'. But the phrase 'it is asserted' suggests an impersonal happening of assertions: 'it is asserted' as 'it is raining' or 'it happens'. The value of the assertion sign is lost if we allow ourselves to revert in our verbal translation of it to the muddle of a declaratory sentence which asserts itself or is impersonally asserted by nobody in particular."