The inhabitants of the kosmos are thus characterized by ignorance, rejection of the spirit of truth, lovers of darkness, workers of evil, and haters of Jesus and his disciples. The ruler of the kosmos is Satan, who has been engaged since Eden in an ongoing cosmic struggle with the Father and the Son for control both of the inhabitants of the kosmos, and the kosmos itself. The Logos/Word has come down from heaven to "cast out" (Jn. 12:31) Satan from the kosmos and bring those who will accept Jesus as the Messiah—thereby accepting his grace, truth, love, and knowledge—back into the light, the presence of the Father, and the unity and love of the Father and Son (Jn. 17). Thus, when the kosmos does not know the Light (1:10), it means that the inhabitants of Satan's world order do not recognize Jesus as the Messiah.
Conclusion
If the fundamental message of the entire Gospel of John could be summarized in one verse it would be this: "For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life" (3:16). John's message is that the Light has come down from heaven to save the world/kosmos, but only those regenerated by the Spirit will recognize this Light and enter the kingdom of God. Those who love the Light will believe in Jesus and receive eternal life.
A pdf file of the full paper, with footnotes, can be found at:
http://byu.academia.edu/WilliamHamblin/Papers/416674/John_3_1-21
or
http://dl.dropbox.com/u/15865520/Enigmatic%20Mirror/EM-John%203%7E1-21.pdf
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