What three classes of people have always existed?

In the
first chapter of Emmanuel Goldstein's
book The Theory and Practice of Oligarchical

Collectivism,reads that the world has been divided into three classes since
the
beginning of time. The three classes of people are the
High, the Middle, and the
Low.

The High
class consists of the privileged, ruling
members, while the Middle class is
made up of citizens who work for the upper-class members of
society. The Low
consists of poverty-stricken individuals at the bottom class of society
focused
on surviving.

Winston Smith proceeds to read that
throughout recorded time,
these three classes have always existed despite
enormous upheavals and seemingly irrevocable
political changes. Winston also
reads that the aims of each of the classes are completely
irreconcilable. The
Middle typically enlists the help of the Low to overthrow the High and

eventually become the High. This cyclical process continually repeats itself throughout
recorded
history as the Middle continually overthrows the High, only to
oppress the Low and new Middle.
Through collectivism, the Party successfully
consolidates power and is able to oppress the Low
for
eternity.