Commencement speeches are rarely profound, so it actually might be worthwhile to bring in a sassy cat. Of course, a hobo might be of use. Or, for that matter, basically anyone who could keep their comments to under ten minutes. Better yet, just get rid of commencement speeches and have plenty of pie as a reward for graduates.
MITTENS: For example, when you are presented with things smaller than you, pounce upon them. Do not obliterate them, but toy with them. Give them small moments of hope to escape. Then, when their hope is highest, descend upon them crushing it.
HOBO: I can't believe students are taking notes. They never take notes in my class!
BEARD: It's just the business majors.