A rate of acceleration of ball have increased when difference of altitude become highly more and more. Water drop from highly more and more, a water turbine revolve quickly more and more. Namely, everything is same high and have a situation of equally and perfectly level born no advantage and no value. Then, the power of human society is difference of wealth and poverty. If every persons are equal position, human society don’t revolve smooth. Ironically, human society become development by difference of altitude from wealth and poverty. So, it is impossible theoretically to become every persons like the same.