Two stupid men on a perfectly ordinary day sat drinking coffee at a coffee bar, discussing about the greatest questions of their time. They sat silently for a long time because they did not know the greatest questions of their time. However, one of them, to the general surprise, came up with an outstanding theory:
'Time travelling is not at all possible,' he declared, dreamily.
'Why so?' the other man asked with a genuine curiosity.
'If I were to, say, design a Time Machine, I'd arrange a rendezvous with myself at some time in the past,' he looked right into the eyes of other man and added 'that hasn't happened till date.'
'Oh,' the other man said; apparently he understood the point and slipped back to his pensive state. There was a long silence before he asked a honest question: 'Then, how do you think we're meeting each other?'
They shared a moment of blackout, and each thought in disappointment: 'Perhaps, we'll never know.'