Coolweb: I can predict the future
ET: Why so can I, so can everyone. It's dead easy. What's hard is to predict AND BE CORRECT.
Henry IV (W. Shakespeare), Part I, Act 3, scene 1:
Glendower: I can call spirits from the vasty deep.
Hotspur: Why so can I, so can any man. But will they come when you do call for them?