What is it?

An increasingly used idiom is "It is what it is." It can be applied to just about anything we don't have control over or can't fully grasp. Wiktionary has these definitions: a thing with its own distinct nature; this thing itself; and as a synonym, the circumstance is simply a fact and must be accepted or dealt with as it exists. It is so ubiquitous and plainly true that anyone or many could have come up with the phrase, but yesterday as I was re-reading Mere Christianity, third chapter, second paragraph those few words popped out at me. CS Lewis in 1943, in his self described search for truth, had written them. Perhaps he was not the first, but from now on, I will attribute those words of wisdom to him.