 Why of these is not a reason Houlihan agreed to help the little people?
Every writer must seek his own Flowery Kingdom in imagination's wide demesne, and if that search can begin and end on Earth his problem has been greatly simplified. A one-time Air Force officer, he has turned to fantasy in his lighter moments, to bring us such brightly sparkling little gems as this. houlihan's equation by ... But its small, mischievous pilots had a rendezvous with destiny—on Earth. It was in a park near the nuclear propulsion center—a cool, green spot, with the leaves all telling each other to hush, be quiet, and the soft breeze stirring them up again. I had known precisely such a secluded little green sanctuary just over the hill from Mr. Riordan's farm when I was a boy. That morning I had been trying to work out an equation to give the coefficient of discharge for the matter in combustion. You may call it gas, if you wish, for we treated it like gas at the center for convenience—as it came from the rocket tubes in our engine. Without this coefficient to give us control, we would have lacked a workable equation when we set about putting the first moon rocket around those extraordinary engines of ours, which were still in the undeveloped blueprint stage. But when you actually put things together, contractions or expansions in the gas, surface roughness and other factors make the velocity a bit smaller. I had to figure everything into it—diameter of the nozzle, sharpness of the edge, the velocity of approach to the point of discharge, atomic weight and structure— Oh, there is so much of this that if you're not a nuclear engineer yourself it's certain to weary you. Perhaps you had better take my word for it that without this equation—correctly stated, mind you—mankind would be well advised not to make a first trip to the moon. And all this talk of coefficients and equations sits strangely, you might say, upon the tongue of a man named Kevin Francis Houlihan. They sounded like small working sounds, blending in eerily mysterious fashion with a chorus of small voices. Not children, but a group of little people, hard at work. I had seen them first as a boy of eight, and then, very briefly again, on my tenth birthday. And I had become convinced they could never be seen here in America. "Come along now, people!" said this crotchety one, looking straight at me.
 He figured he was the only one with knowledge to help them solve their problem
 He saw it as an opportunity to clear his head about his own work  He figured their ship could act as a test case for his work  He felt a kinship with them because of his family's history  He figured he was the only one with knowledge to help them solve their problem