These atrocities soon began to spread general alarm; for no one could perceive any principle or maxim by which they were to be limited for the future; there was on the contrary reason to apprehend that they would be continually multiplied and aggravated. Theramenes, who was endowed with a keen tact which enabled him readily to observe the bent of public opinion, was early aware of the danger into which his colleagues were rushing; and he remonstrated with Critias on the imprudence of creating themselves enemies by putting men to death for no other reason than because they had filled eminent stations, or performed signal services, under the democracy; for it did not follow that they might not become peaceful and useful subjects of the oligarchy, since there had been a time when both Critias and himself had courted popular favour. But Critias contended that they were now in a position which they could only maintain by force and terror; and that every man who had the means of thwarting their plans, and who was not devoted to their interest, must be treated as an enemy. This argument seems for the time to have satisfied Theramenes. But as deeds of blood followed each other with increasing rapidity, and the murmurs of all honest citizens, though stifled in public, began to find vent in private circles, Theramenes again warned his colleagues, that it would be impossible for the oligarchy to subsist long on its present narrow basis. He wished that they might be able to dispense with the foreign garrison, and foresaw that, if they persisted in their present course, they could never safely dismiss it. His advice now produced some effect on them; but they seem to have been alarmed not so much by the danger which he pointed out as by the warning itself. They knew that he was a man who had never adhered to any party which he believed to be sinking, and suspected that he might be meditating to put himself at the head of a new revolution, as in the time of the Four Hundred. And though his character was so generally understood that he had acquired a homely nickname,[2] which expressed the readiness with which he shifted his side, and the dexterity with which he adapted himself to every change of circumstances, still he might again become a rallying-point for the disaffected. To guard against this danger they determined to strengthen themselves by an expedient similar to that which had been adopted by the former oligarchy. They made out a list of three thousand citizens, who were to enjoy a kind of franchise which perhaps was never exactly defined; but one of its most important privileges was, that none of them should be put to death without a trial before the council. All other Athenians were outlawed, and left to the mercy of the Thirty, who might deal as they thought fit with their lives and property.