(when following Wald's work on rearranging series) This is a nice riddle: Is summing the series: 1, -1, 1, 1,.... 0 = (1-1)+(1-1)+(1-1)....=0+0+0... or 1

(when following Wald's work on rearranging series) This is a nice riddle: Is summing the series: 1, -1, 1, 1,.... 0 = (1-1)+(1-1)+(1-1)....=0+0+0... or 1 = 1+(-1+1)+(-1+1)+(-1+1)....=1+0+0+0...