Logos (lō´gŏs) [Gr.,=word], in Greek and Hebrew metaphysics, the unifying principle of the world. The central idea of the Logos is that it links God and man, hence any system in which the Logos plays a part is monistic. The Greek Heraclitus held (c.500 BC) that the world is animated and kept in order by fire—this fire is the Logos; it is the power of order in the world and the order itself. It thus became the unifying feature of the Heraclitean system. The Stoics (see Stoicism) were influenced in part by Platonism and Aristotelianism in their conception of the Logos. To them God was immanent in the world, its vitalizing force, and God as the law guiding the universe they called Logos; with the additional idea that all things develop from this force, it is called the Spermaticos Logos. The Logos reappears in Greek philosophy in a much restricted form in the system of emanations of Neoplatonism. Certain books of the Old Testament present a principle called the Wisdom of God active in the world. At the same time there was a very ancient Hebrew idea of the Word of God, also active in the world. Thus the Wisdom and the Word of God, sometimes quasi-distinct from Him, coalesced. Philo, in his synthesis of Judaism and Greek thought, naturally hit upon the Logos as a union between the systems; hence his Logos retains qualities both of the Stoic Logos and the Hebrew Word of God. Philo's God is remote, unaffected by the world, without attributes, unmoving; hence He must have mediation to connect Him with the world. At times Philo's Logos is independent of God (because of God's remoteness); at other times the Logos is simply the Reason of God (because Philo's monism obliges God to act in the world through His mediating forces). St. John in his Gospel adapted the term to his purpose. In the prologue of 14 verses the idea of the Gospel is stated clearly and simply. The Logos, which is the eternal God, took flesh and became man, in time. The Logos is Jesus. The impersonal, remote God of Philo is not there; the intermediate Logos, neither God nor man, has been replaced by a Logos that is both God and man. This explanation of the relation of God and man became an abiding feature of Christian thought.
See W. J. Ong, Presence of the Word (1967).