At a conference in the Middle East during 2003, if memory serves, this editor heard a familiar voice.
It belonged to a former neighbor, a reservoir engineer seconded by an international major to the host country's national oil company.
A dinner invitation was extended, accepted, pleasurably acted upon.
It happens that a prominent controversy at the time of this accidental and altogether enjoyable reconnection was peak oil.
Many serious thinkers believed global oil production approached the start of irreversible decline. Some thought governments should act to prevent calamity sure to befall the developed world if markets remained unsupervised.
So dinner conversation probably would have turned to questions about future oil supply even if the former neighbor had not divulged that he worked on a team managing production from a giant oil field in the Persian Gulf.
That made a question irresistible: "Now that you've had experience with reservoirs in this part of the world, what do you think about peak oil?"
From there, conversation progressed somewhat like this:
"I don't think about peak oil much," the former neighbor responded with a shrug.
"But how can you not wonder when the field you're managing will run out of oil?"
"I have no idea how much oil's in that field."
"You mean you don't have a reserves number?"
"Sure, but that's just an estimate. What really matters is how many wells the company decides to drill. That's the only effective limit on production."
Back in Houston, this editor performed easy research.
That field has produced oil since the early 1960s. Yet experts privy to the data don't know how much oil remains to be produced.
Experiences like that inform an observation this editor finds himself expressing frequently.
There's a lot of oil in the world.
Sure, oil in nature is finite by some definition of that descriptor. But how finite?
In measurable terms, no one knows.
A couple of hard points follow from these ruminations.
The first is that today's wisdom can become tomorrow's folly.
Even in the physically constrained, lavishly quantified oil and gas industry, thinking changes.
A decade ago, volumetric limitation of oil in nature shaped expectations about the imminent future.
Now, the Organization of Petroleum Exporting Countries reinstates supply management because the market is oversupplied.
And strong reasons exist to doubt the strategy will succeed.
Strong among those reasons is the new ability of non-OPEC producers to raise output quickly from sources unseen not so long ago: unconventional reservoirs.
So how much supply can or will those producers bring to market if OPEC succeeds in elevating the crude price?
That's the question of the moment, is it not?
There can be no answer except in retrospect. Producers in shale and other unconventional plays will respond individually and unpredictably to price movements.
They work with a resource limited less by known volumes of producible oil-what is that number, anyway?-than by the number of wells drilled, like that giant in the Persian Gulf.
Lately, oil prices have risen on mere agreement of OPEC members to cut production. If prices remain elevated, the temptation NOT to cut production will be that much stronger when cuts are supposed to occur.
And producers in unconventional plays will have strengthened incentive to drill and complete wells in reservoirs known to contain oil and gas.
The other hard point is how circumstances of the moment would be different if, when experts felt threatened by The Ultimate Decline Curve, governments had force-fed the market on energy of political choosing.
What was it then? Hydrogen? Or were experts still promising to replace gasoline with methanol from urban waste?
Today the anxiety driving energy politics isn't that oil production will decline inexorably but that it won't decline enough to prevent climatological catastrophe.
There's always something.
And there's still a lot of oil-more, in fact, than anyone thought just a few years ago.