Kestrels, Quirky Birds, and Hopeless Egocentricity

Famed mathematical logical Henk Barendregt calls "egocentric birds" ogres.

There's a simple ogre, YK, but it has no normal form. There are lots of ogres in a different Combinatory Logic bases. The easiest way to find one is to look for "half-ogres", terms that reduce like this: O x y -> O x . An ogre is O O. There may not be ogres that have a normal form in SKI combinatory logic.