All of us have, at some point or other, transgressed morally. Perhaps you've cut in line at the supermarket or fiddled your taxes. Maybe you've dealt drugs in Lan Kwai Fong, taken part in a New Territories small-house scam or given a pro-democracy activist a good kicking. You may even have murdered someone.

Whatever you have done, though, pales into insignificance when compared with the evil perpetrated by the executives of oil and gas behemoth Exxon in the late 1970s and early 80s. If mankind had started acting against climate change then, we wouldn't now have to make wholesale changes to the way we live or invest huge amounts of money to save ourselves from catastrophe. Their actions will almost certainly lead to many lives lost (a toll that is, arguably, already being exacted).

By the late 70s, it's recently been revealed, Exxon's scientists were telling senior management that climate change was real, caused by man and would raise global temperatures significantly in a short period of time. Exxon didn't just ignore the science, it embarked on an active programme of denial, muddying the waters of public perception for a crucial three decades in the interests of short-term profit.

With the Paris climate change conference underway, we should, of course, be optimistic, especially since China, India and the United States have begun to make the right noises, but if it weren't for those greedy oil men, we wouldn't be hoping against hope for a miracle in the coming days.

For what could be the greatest crime of all time, no Exxon executive will face charges and, to rub salt into the wound, their families, cushioned by their ill-gotten gains, will probably weather the climate storm better than most. But let us remember, as the seas rise, storms intensify, crops fail, refugee numbers skyrocket and our lives change radically, a few selfish bastards could have gone a long way to averting it all.