Logos is of course a Greek word. In the Bible it is usually translated as "the Word" but the full meaning is much more complicated. It basically means the reason and order underlying the world. Greek philosophers often referred to what they were doing as giving a logos. A rational explanation of the world. So the logos could also be thought of as the rationality underlying the world.
Philo of Alexandria is the person responsible for bringing this Greek idea together with Judaism. Philo was a Jew who lived and wrote during the time that Jesus is supposed to have lived. He wrote about the religious and intellectual life in Galilee at that time. The fact that he never wrote about Jesus is one of the more damning silences of the historical record about Jesus. If anyone should have written about Jesus it should have been him... But, I digress.
Philo brought this idea of logos together with the idea of Jewish wisdom traditions. John was an inheritor of this new tradition blending Hellenistic Judaism and Greek philosophy.
Here are a couple interesting links on the subject starting with a quote from a gospel translation called "The Complete Gospels".
John 1:1-5
In the beginning there was the divine word and wisdom.
The divine word and wisdom was there with God,
and it was what God was.
It was there with God from the beginning.
Everything came to be by means of it;
nothing that exists came to be without its agency.
In it was life,
and this life was the light of humanity.
Light was shining in the darkness,
and darkness did not master it.
http://encyclopedia.thefreedictionary.com/dict.asp?Word=logosThe Greek word λόγος or logos is a word with various meanings. It is often translated into English as "Word" but can also mean thought, speech, meaning, reason, proportion, principle, standard, or logic, among other things. It has varied use in the fields of philosophy, analytical psychology, rhetoric and religion.
Use in ancient philosophyIn ancient philosophy, Logos was used by Heraclitus, one of the most eminent Pre-Socratic Greek philosophers, to describe the inherent order in the universe and the knowledge men had of each other in Greek society. Logos in Greek means the underlying order of reality of which ordinary people are only unconsciously aware. It is the "Way things are", the totality of the "laws of nature" in the European sense, and, as such, it is always universal (xunos, the common): universal across cultures, though understood differently in each culture via the parochialism of people's expression of, and behavior according to, it -- only if peoples can recognize this.:
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By the time of Socrates, Plato, and Aristotle, logos was the term used to describe the faculty of human reason and the knowledge men had of the world and of each other. Plato allowed his characters to engage in the conceit of describing logos as a living being in some of his dialogues. The development of the Academy with hypomnemata brought logos closer to the literal text. Aristotle, who studied under Plato and who was much more of a practical thinker, first developed the concept of logic as a depiction of the rules of human rationality.
The Stoics understood Logos as the animating power of the universe,
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In Christianity, the prologue of the Gospel of John calls Jesus "the Logos" (usually translated as "the Word" in English bibles such as the KJV) and played a central role in establishing the doctrine of Jesus' divinity and the Trinity. (See Christology.) The opening verse in the KJV reads: "In the beginning was the Word
, and the Word was with God, and the Word was God."
Some scholars of the Bible have suggested that John made creative use of double meaning in the word "Logos" to communicate to both Jews, who were familiar with the Wisdom tradition in Judaism, and Hellenists, especially followers of Philo. Each of these two groups had its own history associated with the concept of the Logos, and each could understand John's use of the term from one or both of those contexts. Especially for the Hellenists, however, John turns the concept of the Logos on its head when he claimed "the Logos became flesh and dwelt among us" (v. 14). Similarly, some translations of the Gospel of John into Chinese have used the word "Tao (道)" to translate the "Logos" in a provocative way.
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http://www.iep.utm.edu/p/philo.htm#H11(snip)
11. Doctrine of the Logos in Philo's Writings
The pivotal and the most developed doctrine in Philo's writings on which hinges his entire philosophical system, is his doctrine of the Logos. By developing this doctrine he fused Greek philosophical concepts with Hebrew religious thought and provided the foundation for Christianity, first in the development of the Christian Pauline myth and speculations of John, later in the Hellenistic Christian Logos and Gnostic doctrines of the second century. All other doctrines of Philo hinge on his interpretation of divine existence and action. The term Logos was widely used in the Greco-Roman culture and in Judaism. Through most schools of Greek philosophy, this term was used to designate a rational, intelligent and thus vivifying principle of the universe. This principle was deduced from an understanding of the universe as a living reality and by comparing it to a living creature. Ancient people did not have the dynamic concept of "function," therefore, every phenomenon had to have an underlying factor, agent, or principle responsible for its occurrence. In the Septuagint version of the Old Testament the term logos (Hebrew davar) was used frequently to describe God's utterances (Gen. 1:3, 6,9; 3: 9,11; Ps. 32: 9), God's action (Zech. 5:1-4; Ps. 106:20; Ps. 147:15), and messages of prophets by means of which God communicated his will to his people (Jer. 1:4-19, 2:1-7; Ezek. 1:3; Amos 3:1). Logos is used here only as a figure of speech designating God's activity or action. In the so-called Jewish wisdom literature we find the concept of Wisdom (hokhmah and sophia) which could be to some degree interpreted as a separate personification or individualization (hypostatization), but it is contrasted often with human stupidity. In the Hebrew culture it was a part of the metaphorical and poetic language describing divine wisdom as God's attribute and it clearly refers to a human characteristic in the context of human earthly existence. The Greek, metaphysical concept of the Logos is in sharp contrast to the concept of a personal God described in anthropomorphic terms typical of Hebrew thought. Philo made a synthesis of the two systems and attempted to explain Hebrew thought in terms of Greek philosophy by introducing the Stoic concept of the Logos into Judaism. In the process the Logos became transformed from a metaphysical entity into an extension of a divine and transcendental anthropomorphic being and mediator between God and men. Philo offered various descriptions of the Logos.
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d. First-born Son of God
The Logos has an origin, but as God's thought it also has eternal generation. It exists as such before everything else all of which are secondary products of God's thought and therefore it is called the "first-born." The Logos is thus more than a quality, power, or characteristic of God; it is an entity eternally generated as an extension, to which Philo ascribes many names and functions. The Logos is the first-begotten Son of the Uncreated Father: "For the Father of the universe has caused him to spring up as the eldest son, whom, in another passage, he
calls the first-born; and he who is thus born, imitating the ways of his father, has formed such and such species, looking to his archetypal patterns" (Conf. 63). This picture is somewhat confusing because we learn that in the final analysis the Creative Power is also identified with the Logos. The Creative Power is logically prior to the Regent Power since it is conceptually older. Though the powers are of equal age, the creative is prior because one is king not of the nonexistent but of what has already come into being (QE 2.62). These two powers thus delimit the bounds of heaven and the world. The Creative Power is concerned that things that come into being through it should not be dissolved, and the Regent Power that nothing either exceeds or is robbed of its due, all being arbitrated by the laws of equality through which things continue eternally (QE 2.64). The positive properties of God may be subdivided into these two polar forces; therefore, the expression of the One is the Logos that constitutes the manifestation of God's thinking, acting (Prov. 1.7; Sacr. 65; Mos. 1.283). According to Philo these powers of the Logos can be grasped at various levels. Those who are at the summit level grasp them as constituting an indivisible unity. At the two lower levels, respectively, are those who know the Logos as the Creative Power and beneath them those who know it as the Regent Power (Fug. 94-95; Abr. 124-125). The next level down represents those limited to the sensible world, unable to perceive the intelligible realities (Gig. 20). At each successively lower level of divine knowledge the image of God's essence is increasingly more obscured. These two powers will appear again in Plotinus. Here Undefined or Unlimited Intelligible Matter proceeds from the One and then turns back to its source (Enneads 2.4.5; 5.4.2; 6.7.17)
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h. The Angel of the Lord, Revealer of God
Philo describes the Logos as the revealer of God symbolized in the Scripture (Gen. 31:13; 16:8; etc) by an angel of the Lord (Somn. 1.228-239; Cher. 1-3). The Logos is the first-born and the eldest and chief of the angels.
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m. Summary of Philo's Concept of the Logos
Philo's doctrine of the Logos is blurred by his mystical and religious vision, but his Logos is clearly the second individual in one God as a hypostatization of God's Creative Power - Wisdom. The supreme being is God and the next is Wisdom or the Logos of God (Op. 24). Logos has many names as did Zeus (LA 1.43,45,46), and multiple functions. Earthly wisdom is but a copy of this celestial Wisdom. It was represented in historical times by the tabernacle through which God sent an image of divine excellence as a representation and copy of Wisdom (Lev. 16:16; Her. 112-113). The Divine Logos never mixes with the things which are created and thus destined to perish, but attends the One alone. This Logos is apportioned into an infinite number of parts in humans, thus we impart the Divine Logos. As a result we acquire some likeness to the Father and the Creator of all (Her. 234-236). The Logos is the Bond of the universe and mediator extended in nature. The Father eternally begat the Logos and constituted it as an unbreakable bond of the universe that produces harmony (Plant. 9-10). The Logos, mediating between God and the world, is neither uncreated as God nor created as men. So in Philo's view the Father is the Supreme Being and the Logos, as his chief messenger, stands between Creator and creature. The Logos is an ambassador and suppliant, neither unbegotten nor begotten as are sensible things (Her. 205). Wisdom, the Daughter of God, is in reality masculine because powers have truly masculine descriptions, whereas virtues are feminine. That which is in the second place after the masculine Creator was called feminine, according to Philo, but her priority is masculine; so the Wisdom of God is both masculine and feminine (Fug. 50-52). Wisdom flows from the Divine Logos (Fug. 137-138). The Logos is the Cupbearer of God. He pours himself into happy souls (Somn. 2.249). The immortal part of the soul comes from the divine breath of the Father/Ruler as a part of his Logos.