"You now know, Kinnison," Mentor mused, "what you children are and how you came to be. You are the accomplishment of long lifetimes of work. It is with most profound satisfaction that I now perceive clearly that those lifetimes have not been spent in vain." "Yours, you mean." Kit was embarrassed, but one point still bothered him. "Dad met and married mother, yes, but how about the others? Tregonsee, Worsel, and Nadreck? They and the corresponding females were also penultimates, of lines as long as ours. Your Council decided that the human stock was best, so none of the other Second-Stage Lensmen ever met their female complements. Not that it could make any difference to them, of course, but I should think that three of your fellow students wouldn't feel so good." "I am very glad indeed that you mention the point." The Arisian's thought was positively gleeful. "You have at no time, then, detected anything peculiar about this that you know as Mentor of Arisia?" "Why, of course not. How could I? Or, rather, why should I?" "Any lapse on our part, however slight, from practically perfect synchronization would have revealed to such a mentality as yours that I, whom you know as Mentor, am not an individual, but four. While we each worked as individuals upon all of the experimental lines, whenever we dealt with any one of the penultimates or ultimates we did so as a fusion. This was necessary, not only for your fullest possible development, but also to be sure that each of us had complete data upon every minute facet of the truth. While it was in no sense important to the work itself to keep you in ignorance of Mentor's plurality, the fact that we could keep you ignorant of it, particularly now that you have become adult, showed that our work was being done in a really workmanlike fashion." Kit whistled; a long, low whistle which was tribute enough to those who knew what it meant. He knew what he meant, but there were not enough words or thoughts to express it. "But you're going to keep on being Mentor, aren't you?" he asked. "I am. The real task, as you know, lies ahead." "QX. You say that I'm adult. I'm not. You imply that I'm more than several notches above you in qualifications. I could laugh myself silly about that one, if it wasn't so serious. Why, any one of you Arisians has forgotten more than I know, and could tie me up into bowknots!" "There are elements of truth in your thought. That you can now be called adult, however, does not mean that you have attained your full power; only that you are able to use effectively the powers you have and are able to acquire other and larger powers." "But what _are_ those powers?" Kit demanded. "You've hinted on that same theme a thousand times, and I don't know what you mean any better than I did before!"