Gustave Le Bon

Under certain given circumstances, and only under those circumstances, an agglomeration of men presents new characteristics very different from those of the individuals composing it. The sentiments and ideas of all the persons in the gathering take one and the same direction, and their conscious personality vanishes. A collective mind is formed, doubtless transitory, but presenting very clearly defined characteristics.

It forms a single being, and is subjected to the Law of the Mental Unity of Crowds.

Taken separately, the men of the Convention were enlightened citizens of peaceful habits. United in a crowd, they did not hesitate to give their adhesion to the most savage proposals, to guillotine individuals most clearly innocent, and, contrary to their interests, to renounce their inviolability and to decimate themselves.