Theo Todman's Web Page - Paper Abstracts

Full Text₁

1. The eighteenth problem is set by Professor Jonathan Harrison of the University of Nottingham under the title 'Jocasta's Crime'.
2. Compulsory reading:
   • "Harrison (Jonathan) - Dr. Who and the Philosophers or Time-Travel For Beginners",
   • "Lewis (David) - The Paradoxes of Time Travel".
3. Miss Jocasta Jones was walking in a secluded part of a local wood when she was attracted by the barking of her dog to a metal object which looked for all the world like an extremely old and rusty deep freeze. She opened it and found inside it a man, alive, but frozen solid. With some help from Miss Jones the man, who called himself Dum, thawed out. He handed Miss Jones a book, which he said told one how to build a time machine² and a deep freeze.
4. Miss Jones, however, was a very feminine creature, and much more interested in men than in engineering. She fell deeply in love with Dum, and married him. After a decent interval they produced a baby whom, because he was the spitten image of his father, they forenamed Dee.
5. When Dee reached maturity, he found the book, which had carefully been put away on a high shelf, out of the reach of children. Following the instructions in it, he built the machine and got inside, taking his father and the book with him, in case he should need some technical assistance on his journey. He pressed the starter button, and, though nothing unusual appeared to happen inside the machine, everything visible through its solitary porthole seemed to start moving in the opposite direction to what it had before, and much more rapidly. The sun rose in the West, and set in the East, backwards day succeeded backwards day, and reverse year followed upon reverse year. The journey was so long that Dee, who had underestimated the amount of food they would need, was reluctantly compelled to make use of his greater youth and strength in order to kill and eat Dum. Eventually Dee arrived at the date which was his preselected destination, and got out. His first act on alighting from the time machine³ had been to blow it up, and everything contained in it, including what little remained of Dum.
6. Dee, however, had not been happy in his new environment. The guilt he felt for what he seemed to remember he had done produced a mild attack of paranoia, which was accentuated by the loneliness of his position. He had wandered forlornly about, obsessed with the thought, which even changing his name to Dum could not eradicate, that despite his having destroyed the evidence, the men he now lived with could not fail to discover and severely punish him for his unnatural action. To escape he built the deep freeze, and got inside. He was prudent enough to take with him the book, in case he needed to build himself another time machine⁴ or deep freeze at an earlier or later date.
7. The next thing Dum remembered was being resuscitated by a Miss Jocasta Jones, who had been exercising her dog in the neighbourhood...
8. Did Jocasta₅ commit a logically possible crime?