As the famous cartoon to the right shows, our views of the world have a tendency to be limited to the range of our experience (as they should), but we should always be aware that there's probably more to reality than what we can experience, and that the possibility of new discoveries is not simply a thing of the past: our science is still in its infancy, and that means that most of what's left to be discovered is still out there, waiting for the next creative person to figure out how to find it.
In the following video, Jorge Cham (creator of PhD Comics) talks with two astrophysicists about dark matter and how the Large Hadron Collider will help answer what it is. And, by the way, the whole thing is animated (sort of) RSA Animate style:
To me, the mystery isn't so much how much is still left to discover... it's how much we already have...
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