THE COMPLEX ARGUMENTS surrounding the morality of cage-diving with great white sharks tend to be lost on you when youre in the shark cage. At this stage, your mind is occupied by things that are slightly more fundamental - mainly the dark shadow that is looming out of the atmospheric mix of chum and murky water in front of you.
No matter how experienced a diver you are, no matter how much of a shark fanatic, no matter how much the logical portion of your brain reassures you that you are terribly well protected, there is a substantial part of you that gibbers in fear.
This is the part that is still the primaeval man, the hunter-gatherer that lurks just beneath the veneer of civilisation that covers most of us. This primitive part of our brain tells us that we are in the presence of an animal that can kill us, can hunt us down with an effortless sweep of that broad tail, and can consume us without a flicker of emotion in that dark eye.
Its an odd feeling, and certainly an addictive one. Hence the booming industry in lowering ashen-faced tourists, both divers and non-divers, into cages that are being slowly circled by the most magnificent predator on Earth - one that captures our imaginations like no other.
Why do we do it Why fly across the world to clamber aboard a wildly rocking boat wreathed in diesel fumes and reeking of chum, to climb wide-eyed into a cage in cold water to peer myopically at what - after all is said and done - is a big fish
The reasons are at once complicated and, at the same time, wonderfully simple. Chat to those same tourists returning from the dive, and at a superficial level there are a variety of motives for diving with the sharks, ranging from passing curiosity to a life-long obsession. Thats the complicated part - we all have our reasons for wanting to do it, and thats very much our own business.
But there is a very simple reason, too. It wasnt so long ago that we were charging off to hunt woolly mammoths and eat berries with hairy fingers. Like any animal in the gene pool, we wanted to pass on our floppy disc of genetic odds and bobs intact to the next generation.
To ensure our ability to do so, we had to survive for long enough to grow to the right age and meet another hairy person to do what came naturally - and all before alcohol was invented.
The definition of biological success is to survive to a breeding age, and to do so we needed to garner knowledge of our greatest predators, the small selection of animals that have the equipment (and occasionally the desire) to hunt us actively.
In the most basic way, we are fascinated by big predators because they can remove us from the gene pool. Knowledge is survival - and even in the age of a civilisation so advanced that it has brought us not only Countdown but also Richard & Judy, we remain fascinated by our enemies in the animal kingdom. In the most basic sense, we love our predators as much now as we ever have.
Once the initial fear has passed, in that first heart-stopping encounter, most people simply cant get enough of cage-diving with the great whites.
Close passes to the cage are greeted with wide-eyed wonder, while spectacular predatory thrashing on the surface as the operators wrestle the baits from gaping jaws are greeted with great shouts of acclaim and the whirring of motor drives.
The arguments surrounding the morality of cage diving are where things get really convoluted, and they are now reaching a crescendo, given the spate of recent serious incidents involving great whites and people in the water.
Superficially, it would seem easy to explain - an increase in the number of serious attacks by great whites has mirrored the rise in the cage-diving industry over the last decade. Surely luring great whites towards boats by creating a chum slick, then popping people into cages in full view of the animal, must create a strong association between the presence of people and food
Is the result a triggering of the feeding response when a human silhouette is sighted in the water Certainly a number of surfing groups think so, and they are lobbying hard to get the industry banned in places such as South Africa.
But there are compelling counter-arguments. Speak to most of the fishermen along any stretch of coastline patrolled by great whites, and they all have stories of regular sightings of big sharks around their boats.
For centuries, fishermen have been hauling in thrashing nets packed with fish, the water around their boats a mist of slime and fish blood - an irresistible dinner gong for any great white in the vicinity.
For just as long, they have been gutting their catch on site, throwing the guts into the water around the boat and creating an instant buffet for any sharks that have turned up. Saying that the cage-diving industry has created a new association for the sharks between boats and food is simply not true - weve been doing that for as long as the fishing industry has existed.
What is undeniable is that recent incidents have increased, but then again, so have certain populations of great whites.
Protected in South Africa since 1991, with the rest of the world following suit over the next decade or so, great whites enjoy protected status in inshore waters on a larger scale than ever before.
Of course, this doesnt help them against the scourge of the long line in the open sea, where sharks are being culled as never before - but evidence does exist of the recovery of some great white populations. And there are those who claim that those enlarged populations are finding less to eat as a result of fishing industry activity, and are being forced to come in closer to shore in their efforts to find food.
In the early 1990s, the area around Dangerous Reef in South Australia was virtually devoid of great white sharks, as the animals succumbed to brutal overfishing and exploitation.
A well-financed filming expedition in this period sat over the reef for three weeks chumming continuously and saw only three great whites, all of which were too skittish to be filmed.
The Rodney Fox operation reports that numbers have increased dramatically since the sharks gained protected status in these waters in 1998.
Sports such as surfing, windsurfing, kite-surfing, and diving are more accessible now than ever before. This means more of us frolicking in the coastal fringes than at any other period in the history of mankind.
By unhappy coincidence, legislation passed protecting the great white was brought into force about 15 years ago, and has possibly allowed a considerable population of great whites to grow to a considerable size.
So is it simply a case of moresubstantial great whites coming into contact with more people as we use the sea as a playground on a massive scale
What is undeniable is that the cage-diving industry is exposing more people to this magnificent animal than ever. The populations of great whites off the coast of cage-diving hotspots are jealously protected by the operators.
Interestingly enough, perhaps the most dangerous thing you could do with a great white off Gansbaai is kill it. The resulting sustained beating from some substantial local gentlemen who regard these animals with real affection would leave you in no doubt as to their strength of feeling. Can it be said that great whites are starting to be regarded with more reverence and awe - rather than hatred and fear - because of the activities of the cage-diving industry
The only thing that can be stated with certainty is that arguments surrounding the connection between cage-diving and an undeniable increase in great white attacks are very complex. It is a simple reflex action to point the finger at cage-diving, but it is crucial to investigate the myriad factors that have changed for both us and the great white over the past 20 years before the line connecting the two becomes anything other than purely speculative.
To condemn the cage-diving industry out of hand may well be to threaten the greatest shop window this magnificent, misunderstood animal has ever had.

More and more people are willing to pay for this sort of experience - and the sharks are getting bigger, too