The book "Introduction to Ancient Philosophy..." by the famous English historian of philosophy Arthur Hilary Armstrong is based on lectures given by him at the Newman Association philosophical society in 1943. In it, the author refers to the origins of Christian thought, which he sees in pagan philosophy and, above all, in Socrates, Plato, Aristotle and Plotinus. Armstrong focuses on the philosophical searches of antiquity, directly adjacent to the "conduct" of Christian theology, namely: the development of the doctrine of the Logos from Heraclitus to Plotinus, Socrates' doctrine of the soul as a rational person, Plato's theory of Ideas and theology, Aristotle's metaphysics and the philosophy of Neoplatonism.