These varnas and asramas have their respective duties, and unless human society is divided according to these eight scientific divisions and everyone acts according to his position, there can be no peace in the world.

varnasramacaravata
purusena parah puman
visnur aradhyate pantha
nanyat tat-tosa-karanam

“The Supreme Personality of Godhead, Lord Visnu, is worshiped by the proper execution of prescribed duties in the system of varna and asrama. There is no other way to satisfy the Supreme Personality of Godhead.” (Visnu Purana 3.8.9)

Srila Prabhupada — Teachings of Lord Kapiladeva, Vs 3, Text 3