No doubt you have seen it in many films, the image of the attorney who stalks the courtroom and declares: "We will show beyond a shadow of a doubt . . ." You will also often have read: "Scientific research has proved . . ."
Both these phrases allege a hold on the truth but lawyers and scientists go about achieving "proof" in different ways. This is illustrated by the work of the two principal investigators of the Loch Ness monster phenomenon. The story is recounted in the New Yorker (November 27th, 2000).
Loch Ness is located about 11km southwest of Inverness. It is part of the Great Glen which virtually splits Scotland in two from east to west. Ness is the largest of three lakes in the glen. Covering 14,000 acres, it is almost 39km long and up to 1.6km wide.
There is scarcely a person in the developed world who has not heard of the Loch Ness monster. Records recount that the beast was first encountered by St Columba in 565 AD, but the phenomenon didn't really take off until 1933 when a Mr and Mrs MacKay reported seeing a massive creature disporting itself in the lake for over a minute. The following year the first photograph of the creature was taken, seeming to show the head and neck of a plesiosaur-like creature rising from the water.
Many sightings have since been reported and quite a number of photographs have been taken. The sightings are reported by people from all walks of life. Investigators accept that most of these witnesses are convinced that they saw the creature. However, the photographs of Nessie (as the creature is affectionately dubbed) are no better than suggestive of a large, long creature with a small head and long neck. Apart from this there is no physical evidence that Nessie really exists.
What might Nessie be if it does exist? Theories abound and include a prehistoric snakelike whale, a giant eel, an unknown type of long-necked seal, a walrus or a mirage.
The favourite contender is the plesiosaur, a marine reptile which has officially been extinct for the past 70 million years. This choice might seem unlikely if it weren't for the coelacanth, a fish thought to be extinct for 70 million years until it was found thriving in the Indian Ocean in 1983.
Bob Rines and Adrian Shine are two major investigators of the Loch Ness phenomenon. Rines trained as a physicist and engineer and works as a patent lawyer. He is a well known inventor of high-resolution sonar equipment. Shine is a scientist.
Rines and Shine approach the monster in very different ways. Rines actually saw Nessie in 1972. He describes a large hump, about 25ft long, covered in mottled skin, which moved about for a while and then submerged.
Since then he has hunted Nessie using a sophisticated underwater sonar device coupled to a camera. The proximity of any large creature triggers the camera into action. This device produced some spectacular photographs of a "flipper" and a "plesiosaur head", three of which were published in the science journal Nature in 1975. However, many people have since dismissed these photographs as pictures of debris on the lake bottom when the camera drifted into shallow water.
Shine also began his investigations in the early 1970s. Very early on he thought he saw Nessie, but closer inspection revealed only a rock. Shine became very sceptical. In 1989, he organised what he hoped would be the definitive search for Nessie, Operation Deep Scan.
Thirty motor launches equipped with sonar formed an unbroken line across the lake and proceeded systematically down its length scanning for large objects below. No monsters were revealed. Believers in Nessie have countered that the creature was hiding in a cave.
Rines takes a legal approach towards evaluating the evidence; Shine takes a scientific approach. Rines believes that if the case of Nessie was tried in a court of law, the existence of the creature would undoubtedly be upheld. Rines will use all the physical evidence he can muster but he also lays considerable store in the eyewitness accounts.
The scientific approach is different. A hypothesis is proposed to explain the phenomenon and then it is tested by experiment. The experiments are designed to challenge the hypothesis - to disprove it. If the hypothesis continues to defeat all challenges then confidence builds that the hypothesis is correct. If the hypothesis is defeated by a fair challenge then it is rejected.
The hypothesis is that Nessie exists. If this is true then the creature must be detectable, but science finds none of the evidence of detection (sightings, photographs, sonar probes etc) convincing. This leads to the heart of the difference between the legal and the scientific approach - confidence in eye-witness testimony.
A court of law would place much weight on the fact that so many people have seen a large creature in the loch. Science does not weigh the eye-witness evidence so heavily.
Our eyes tell us the world is flat and the sun resolves around a stationary earth but science must probe beyond what the eye records. This is a powerful approach, but it carries a down side. It appears cold and one-dimensional to the non-scientist.
If Nessie exists it is clearly very reclusive and, probably, only science has any real hope of revealing the creature to us. I hope Nessie exists and that science will show it to us because a world with Nessie is more wonderful than a world without.
William Reville is a senior lecturer in biochemistry and director of microscopy at UCC