Across the hall and to your left...

It's 8:08 and I'm already annoyed. Man enters cubespace.
Man: "Do you know where is my PD [professional development]?"
[Note: Today's PD's and meetings are all posted right in front of him, as well as in several places around cubespace]
Me: "Which one?"
Man: looks at me, shocked. "I don't know which one."
Me: "Sir. Who are you and why are you here then?"
Man: "I... I..."
Me: "We have several PDs available for your enjoyment today. Please view and choose...." I point to one of the signs.
Man stands and stares for 5 minutes then says, "oh, I am a psychologist. Does that matter?"
Me: "Yes. You must be here for the Psychologists' PD in the 7th floor large conference room, across the hall and to the left. Please go there now."

People have continued to file in and interactions have continued in a similar manner. Why intelligent, seemingly well-educated people don't read signs, I don't know. I think it may be a long day.