I think we've just hit a semantic obstacle, but we can leap over it. I think I see what you mean, Netti: I must have some truth, and I must embrace truth. That is also close to the sense in which the synoptic gospels treat truth and light, but it is not the way that John uses light in his writing. He uses light to emphasize a completely different point about humans and truth. I agree with you that truth has to be important to individuals. I also think John agrees with your intent, however his choice of words is different. To read his verse, 'Light' means something not human. In the three synoptic gospels, the disciples are a light, according to Jesus, when they do good works. Conversely in John's writings we walk in light rather than being a light source, and the light judges our works. To him, our good work is our walk, and light is something else. It is not a problem: there are just two different uses for light going on. John is not saying that men cannot have any truth but that they can not claim to be a source of it. James also emphasizes this. They both go to some trouble to explain that we should make it clear that we are not the light source, because we are imperfect. John's books share some singular usages and ideas apart from the 3 synoptic Gospels of Mathew Mark, and Luke. John's usage of the work 'Light' is the most noticeable difference. In the synoptic gospels Jesus says things like "You are the light of the world." In John, Jesus does not say this; and usage of the word 'Light' is specially reserved for the Son. (A similar preference is detectable in James.) John's light is a light which judges the world. John emphasizes the error in men, contrasting their words against the perfect light that judges men. In James we get the same emphasis. Here light is what gives men power to become sons of God -- the pure truth from God, and it gives life. John 1:8 He himself was not the light; he came only as a witness to the light. John 2:8 Yet I am writing you a new command; its truth is seen in him and you, because the darkness is passing and the true light is already shining. James 1:17 Every good and perfect gift is from above, coming down from the Father of the heavenly lights, who does not change like shifting shadows.