Which is a central concept in buddhism? rituals castes service sacrifice

A central concept in Buddhism is RITUALS.

Buddhism's main goal is to achieve a state of lasting happiness known as enlightenment. In order to aid the journey, a variety of rituals and practice are essentials. Some of them include meditation, mantras (Sacred sounds), mudras (Symbolic hand gestures) and Prayer Wheels (To recite mantras with the turn of a wheel), all of which helps to induce an altered state of consciousness, be present, be mindful, etc.

"the attempts of the proletariat to rise above this abasement"

i think you may have asked this twice, but i answered one of the