"I thought everything would be rosy from that point on, but it wasn't. I found that I couldn't keep up with the mail unless I worked impossible hours. I added a couple of new pieces of equipment to the control section. One was simply a huge memory bank. The other was a comparator circuit. A complicated one, but a comparator circuit nevertheless. Here I was working on instinct more than anything. I figured that if I interconnected these circuits in such a way that they could sense everything that went on in the plant, and compare one action with another, by and by the unit would be able to see patterns. "Then, through the existing command output, I figured these new units would be able to control the plant, continuing the various patterns of activity that I'd already established." Here Lexington frowned. "It didn't work worth a damn! It just sat there and did nothing. I couldn't understand it for the longest time, and then I realized what the trouble was. I put a kicker circuit into it, a sort of voltage-bias network. I reset the equipment so that while it was still under instructions to receive orders and produce goods, its prime purpose was to activate the kicker. The kicker, however, could only be activated by me, manually. Lastly, I set up one of the early TV pickups over the mail slitter and allowed every letter I received, every order, to be fed into the memory banks. That did it." "I--I don't understand," stammered Peter. "Simple! Whenever I was pleased that things were going smoothly, I pressed the kicker button. The machine had one purpose, so far as its logic circuits were concerned. Its object was to get me to press that button. Every day I'd press it at the same time, unless things weren't going well. If there had been trouble in the shop, I'd press it late, or maybe not at all. If all the orders were out on schedule, or ahead of time, I'd press it ahead of time, or maybe twice in the same day. Pretty soon the machine got the idea. "I'll never forget the day I picked up an incoming order form from one of the western jobbers, and found that the keyboard was locked when I tried to punch it into the control console. It completely baffled me at first. Then, while I was tracing out the circuits to see if I could discover what was holding the keyboard lock in, I noticed that the order was already entered on the in-progress list. I was a long time convincing myself that it had really happened, but there was no other explanation. "The machine had realized that whenever one of those forms came in, I copied the list of goods from it onto the in-progress list through the console keyboard, thus activating the producing mechanisms in the back of the plant. The machine had done it for me this time, then locked the keyboard so I couldn't enter the order twice. I think I held down the kicker button for a full five minutes that day." "This kicker button," Peter said tentatively, "it's like the pleasure center in an animal's brain, isn't it?"