ARMAND LINKMULLER' 84 trooped into Memorial Hall the morning of registration, walked up to the table marked "G-M" and asked for his package.

"What was the name again?" the woman handing out the packets asked.

"Linkmuller. Armand Linkmuller."

"That's an unusual name, isn't it? Let's see. Linemiller. Lingmallen. Linkalook. Here it is. Linkmul--" The woman fainted in mid-word, dropping the packet.

As Armand watched in bewilderment, two workers tried to revive their fallen colleague while a third noticed the cause of the commotion--Armand's registration envelop. She looked down at the package, up at Armand, down at the packet again and started shaking. "The purple dot--it's him!" she screamed.

Armand snatched his registration package and saw that she was right: a small purple dot adorned the top of the envelope next to his name.

"Just stay right there," a registration worker yelled at Armand, while other workers tried to evacuate the hall. He reached under the table and pressed an alarm button. All around the "G-M" table red lights flashed, sirens blared, and registration workers sprayed disinfectant. Within seconds, two men in white uniforms sandwiched Armand.

"What's going on?" the confused freshman asked.

"We're taking you away."

"Why?"

"Because you're it."

"I'm what?"

The man looked down at Armand and frowned. "The Mistake."

AS THE MEN carried him off, Armand thought back to the first Sunday of Freshman week, when an administrator had told the members of his class gathered in front of Mem Church that, as hard as they tried to avoid it, the admissions office made one mistake every year. Armand had laughed with everyone else, but privately he wondered if there weren't some truth in what the administrator said.

From the moment he arrived in Cambridge, things had not gone well for Armand. A letter sent to his home informed him that his room for the year was University Hall 5. Armand reported there and greeted the receptionist.