There is a tide in the affairs of men, Which, taken at the flood, leads on to fortune; Omitted, all the voyage of their life Is bound in shallows and in miseries; On such a full sea are we now afloat; And we must take the current when it serves, Or lose our ventures. Shakespeare.Julius Cæsar, Act IV. Scene 3. (Brutus to Cassius just before the battle at Philippi.)