N(N>1) natural numbers are taken in turn to form a group of finite series, in which the odd series and even series are obviously shorter than the natural series. But if the natural sequence is extended indefinitely, the odd and even series must be smaller than the whole. In an infinite world, the part may be equal to the whole.
In the infinite world, the part must not be equal to the whole cannot be a logical corollary of the above conclusion.