"They call great men 'great lights.' 'And then came the light,' they say, regarding the solving of some great thing. 'He brought the light'--that's what I wanted to do! They tell about science bringing the light. I know now what a tribute they pay when they say that. Light of understanding, light of truth--and ah, mein liebchen, the light of love--and well do I know how that light can shine into the darkness! "'More light'--Goethe said, when he was going out into the dark. A great thing to ask for. I know how he felt!--'And God said--Let there be light'--I don't wonder that story has lived a long time. "My books are finished. Now what?--more books?--lectures?--some kind of old woman's make-shift? Sit here and watch my red blood dry up? Sit here like a plant shrivelling away in the darkness? Be looked after and fussed over and have things made as easy for me as possible? I don't know--I can't see-- "There, liebchen--I've taken a brace. I took a long drink of courage, and I'm in better shape. Often when I get like that I've been tempted to take a long drink of something else--but I never have. Whiskey's for men who feel good; men who haven't much to fight. Not for me--not any such finish as that. "I'm making bad business of this letter. I wanted to tell things, tell what light was and what darkness was; but I can't do it. Many things have been circling around my thoughts and I thought I might get hold of a few of them and pull them in. But I can't seem to do it. I never was much good at writing things out; it's hard to get words for things that aren't even full-born thoughts. "My work was great, liebchen--great! A constant piercing of the darkness with light--a letting in of more light--new light. I can understand now why I loved it; where the joy was; what it was I was doing. "Is life like that? Don't we understand things until we are out of them? By Jove, is it true that we have to _get_ out of them, in order to understand them? And if that's true, is it the understanding that's the goal? Is it--oh, I don't know--I'm sure I don't know. "But look here, liebchen,--is it true that while I had the light, I didn't have it at all,--didn't know what it meant? Did I have to lose it in order to get it? For isn't it _having_ a thing to understand it--more than it's having it to really have it and not understand? See what I mean? Those are some of the things circling around on the outside. "Sometimes I think so. Sometimes I think the light was shut out that the greater light might come. Sometimes I think we scientists haven't the right line on the world at all. Why, Ernestine, sometimes I think it's miles deeper than we ever dreamed! A hodge-podge--this letter. Like my life, starting out one thing, and ending up another, or rather not ending up anything at all--a going to pieces in the midst of my philosophy--a not being sure of anything--a constant 'perhaps.'"