Curse you, thermodynamics! You win again!
It's well known that the laws of thermodynamics forbid the creation of a "perpetual motion" machine - that is, any device that can run forever without any external power source. Many attempts have been made to get around this, but they've all proven to have some fatal flaw.
Many creative thinkers believed that the problem had finally been solved for good with the design of the CBTD, or Cat Buttered Toast Device. I first heard of the CBTD at least fifteen years ago. This ingenious creation is based on two laws of nature even more inviolable than those of thermodynamics:
- A piece of buttered toast, dropped on the floor, will always land buttered-side down.
- A cat dropped on the floor will always land on its feet.
The CBTD consists, quite simply, of a piece of buttered toast strapped buttered-side up to the back of a cat and dropped on the floor. By the laws of the universe, it cannot land cat-side down because then the toast would be buttered-side up, but it can't land toast-side down because then the cat would not be on its feet. The CBTD must therefore hover above the floor, spinning endlessly trying to resolve the dilemma.
Many scientists have pondered the CBTD over the years and almost all have come to the conclusion that it is indeed flawless - the holy grail of a perpetual motion machine has finally been discovered. (Animal rights activists have, sadly, succeeded thus far in preventing any experimental verification).
In the past 24 hours, however, research into the matter by a new entrant in the field has led to an extraordinary breakthrough, proving indisputably once and for all that the CBTD is doomed to failure. Careful observation of many cats has led to confirmation of the radical notion that cats like the taste of butter. Therefore, when strapped to a piece of buttered toast, the cat (possessing as it does considerable flexibility and a keen sense of smell) would inevitably lick the butter off the toast. Thus, the CBTD can only spin a few dozen times in mid-air before the toast, deprived of butter, becomes free to land either way up.
Thermodynamics has foiled us again! But it will be defeated eventually. After all, it was widely believed that nothing could travel faster than light, until that was firmly disproved - to the disappointment of scientists and normal human beings alike - by the discovery of PHSVT (Paris Hilton Sex Video Theory).