Susan's look was sympathetic. Steve didn't understand. It wasn't as difficult for him as it had been for her teachers when they first entered the TARDIS.
"Let's say you were putting together a clock," the boy started more slowly. Sometimes it helped him to explain things as if he were talking to a very small child. "This clock is important. It keeps the time for all of your people. Only certain parts will do. The more parts you put in, the better it is at helping your people, but you still must be very careful and selective..."
Was it clear to him yet? Susan frowned.
"When each part is selected, it must be polished or bent or made sure it will do it's part. On its own, it might seem broken or odd, but when used in conjunction serves a specific purpose. Those that look into the Untempered Schism come out exactly as they're supposed to, for the greater good. If Gran had taken me after my initiation, it would be a much greater crime."
Susan hoped that helped.
"This place? May I guess what it is?" He smiled. It was like a game for Susan, having seen so little and only heard a bit of conversation between Steve and Natasha. "It's a secret place. You're a soldier, right? And you train soldiers here? Since it's secret..."
He thought about it carefully.
"...We must not be in the Age of Miracles yet. Your soldiers are special though, aren't they?"