The paper offers a reconstruction of Antisthenes’ understanding of practical wisdom, based on the comparison of doxographic reports on Antisthenes with Xenophon’s portrait of the philosopher. The comparison shows that Antisthenes links wisdom with perseverance and self-control – with an asceticism that results in excellent decisions. The therapeutic function of wisdom consists in eliminating all deceptive assumptions about what it means to live a good life. However, wisdom alone is not enough for anyone to live a happy life. Wisdom requires Socratic education, i.e. instructions concerning our attitudes to others as well as ourselves.