Kautsky should certainly have been able to recognize a socialist when he saw one.
Plutarch’s life of Lycurgus led the early socialists to adopt him as the founder of Spartan “communism” – this is why Kautsky lists him. But as described by Plutarch, the Spartan system was based on equal division of land under private ownership; it was in no way socialistic. The “collectivist” feeling one may get from a description of the Spartan regime comes from a different direction: the way of life of the Spartan ruling class itself, which was organized as a permanent disciplined garrison in a state of siege; and to this add the terroristic regime imposed over the helots (slaves). I do not see how a modern socialist can read of the Lycurgan regime without feeling that he is meeting not an ancestor of socialism but a forerunner of fascism. There is quite a difference! But how is it that it did not impress itself on the leading theoretician of social-democracy?
Pythagoras founded an elite order which acted as the political arm of the landed aristocracy against the plebeian-democratic movement; he and his party were finally overthrown and expelled by a popular revolutionary rising. Kautsky seems to be on the wrong side of the barricades! But besides, inside the Pythagorean order a regime of total authoritarianism and regimentation prevailed. In spite of this, Kautsky chose to regard Pythagoras as a socialist ancestor because of the belief that the organized Pythagoreans practised communal consumption. Even if this were true (and Kautsky found out later it was not) this would have made the Pythagorean order exactly as communistic as any monastery. Chalk up a second ancestor of totalitarianism on Kautsky’s list.
The case of Plato’s Republic is well-enough known. The sole element of “communism” in his ideal state is the prescription of monastic-communal consumption for the small elite of “Guardians” who constitute the bureaucracy and army; but the surrounding social system is assumed to be private-property-holding, not socialistic. And – here it is again – Plato’s state model is government by an aristocratic elite, and his argument stresses that democracy inevitably means the deterioration and ruin of society. Plato’s political aim, in fact, was the rehabilitation and purification of the ruling aristocracy in order to fight the tide of democracy. To call him a socialist ancestor is to imply a conception of socialism which makes any kind of democratic control irrelevent.