It's the feast day of St. Dominic. Without Dominic, we may not have had St. Thomas Aquinas. And without St. Thomas Aquinas, we wouldn't have had GKC's splended biography: St. Thomas Aquinas: The Dumb Ox.
So that's why we oughtta celebrate today's feast day.
(Alright, so maybe I've gotten all the priorities backwards, but still: it's a great book. One of my favorites of all time.)