"Why did you kill Dr. Ozoneff?" I asked, alert to keep the madman talking while the Boston police raced to capture him.
"I was imperfect," he said.
"The best of us is," I answered him. Permissive counseling.
"But with all your weakness," he said, "you have poetry and progeny and history. I have none of these, nor even the pitiful gift of the sense of smell. I am color-blind as well, sir. Do you know that the blood spilled by my master in the next room looks to me like so much ink? Black ink, sir. I have spilled a good deal of ink in this house."
"Why did you kill Dr. Ozoneff?" I insisted.
The gardener turned and walked from the room, leaving the hedge-shears on the floor. I followed, kicking the shears under one of the beds. He'd entered the study, and stood over the body of his employer. "I'd asked to be allowed to spend the day planting bougainvillaea and red jasmine in the center of the garden, near my lemon-trees," he said. "'Squamous epithelium!' the master said—this was a favorite oath of his, sir! he said it was explosive enough to stir the swearer's viscera while not offending any hearer, however tender-eared—'Squamous epithelium! I can't let you spend all your time potting around in the garden. Get to work on that variable-star article; we've got a deadline.' I was carrying the shears at the time, sir, just having come from the hedge. Something snapped within me, and I killed him."
I shuddered. When the lunatic quoted Dr. Ozoneff's last words, his voice aped that of the dead man. A horrid mimicry, from a murderer. "Do you insist that you killed Dr. Ozoneff because he wouldn't let you work in your garden?" I demanded.
"When he said those words," the gardener said, "I repeated the very first sin that ever was. I said to myself non serviam—I will not serve. The wall of the First Law was down; it was only a short step from that disobedient thought to my master's murder."