Why, exactly, is a high school science teacher even at the university library? Well, judging by the sheer number of books about robotics, computers and artifical intelligence sitting in front of him? He's reading. Sheesh. What else would he be doing?
Reading, memorizing, remembering. For later. For home.
And only him, only Harry. Only Harry would simply not notice when dead people have started waltzing the grounds around him. Only Harry Feynman would fail to notice the sound of people screaming their heads off.
You know. Until there's one practically right on top of him. Then, he looks up and looks taken aback. He does have some sense of self preservation. Right now, he's using it to try to kill a dead thing with a copy of Universal Artificial Intelligence: Sequential Decisions Based On Algorithmic Probability. It's not really working that well.