Which part of the neuron sends messages to other neurons?

Axon

An axon is part of neuron with long single fiber that sends messages to the dendrites of other neurons. They transmit information away from the cell body and may have myelin covering to protect the axon and help to fasten the speed of transmission of the signal that deliver the message to other neurons, tissue like the muscles and organs.

you did not attach the discourse, but i assume it to be the discourse on the origin and basis of inequality among men (the original titile in french is: "discours sur l'origine et les fondements de l'inégalité parmi les hommes"), also know as "second discourse". in this discourse, jean-jacques rousseau emphasizes that private property is the basis of all inequalities.

therefore, what enabled the old regime to maintain as long as it did was private property.