He and I observe the same world (only difference, he is much more intelligent), but we come to very different solutions to life's problems. Which of course reveals another difference–humans are limited by the extent of our knowledge. There is a ceiling, so to speak, that prevents us from grasping full knowledge. Full knowledge can only be ascertained by an outside source revealing it.
After watching his video, it struck me that everybody has a theology of God, theology of salvation, and theology of eschatology. Of course the categories, definitions, terms, and frameworks are viewed from very different focal points with the aid of very different lens. For instance, how one responds to the question, "Who is Jesus?" reveals much about how you view God, humanity, and the world.
Tim Keller's presentation, "Who is this Jesus?" offers a vivid contrast to Sam Harris' presuppositional starting points. You can download it for free by clicking the link or listening to it in the embedded player.
I encourage you to listen to both Tim Keller and Sam Harris. What are each offering the listener in their presentation? What are the future ramifications in the world if one of them is correct and the other wrong?
[UPDATE: I cannot figure out how to get the player to work. Please click the "download" link to stream it.]
The below video was embedded from TED: Ideas Worth Spreading:
(the irony of me sharing this video is that I don't consider the presentation's implications worth spreading)