Using the principle that the best theatre changes lives, it is easy to have conflicting views about ten billion.
This powerful PowerPoint lecture from Stephen Emmott is likely to change the life of this critic, at least briefly. However, even its director, Katie Mitchell might be hard-pressed to convince cynics that the hour-long event is theatrical.
The laid-back Professor with a Yorkshire accent certainly has a serious topic. The future or not of our planet should make viewers take note and the conclusions are worthy of a horror story.
The lecture is delivered from the comfort of a simulacrum of the Professor's office at his Cambridge lab, with one wall left blank to receive projections and predictions of doom. His delivery comes courtesy of a laptop, which supplies prompts if not every line of text and benefits from occasional flashes of a very dry wit.
The message is all. The population of the earth has grown from 3bn to 7bn in the last fifty years and could hit 10bn in the next couple of decades.
While having more company might seem desirable, when we have been raping global resources for generations, crisis is approaching.
Much of the information relayed is depressing, showing that every kind of resource will run short as we eat and drink our way into oblivion.
As an example, the statistics on water beggar belief, a single burger requires a swimming pool of water and even a 1 litre bottle of water takes 4 litres to produce.
Between pollution and consumption, which form an ever-repeating circle of disaster, we are rapidly depleting the planet's resources and it is only going to get worse.
As the lecture began to draw to its close, all that was left for our guide to do was tell us the way we could resolve our little problem about how to have a future after drought and flood have destroyed countries and climate migrants replace their economic grandparents.
Professor Emmott, whose main employer is one of those global megacorporations that is currently threatening the planet (they all are), has a deceptively effective style of delivery and structuring of his material which means that even laymen will not suffer from information overload.
They may well be left in an almost suicidal state on realising that without collective efforts of most of the ten billion, matters are only going to get worse as climate change makes life intolerable for the 28bn population predicted for 2100.
While anyone seeing the lecture will be tempted to cut out hamburgers, air travel and lean towards recycling for a bit, they may be so overwhelmed by the enormity of the problem as to take the fatalistic view that nothing individuals do will make the slightest bit of difference so let's party on.
Sadly but predictably, there is no answer other than that firm belief favoured by all unsuccessful gamblers that the next roll of the dice will provide the solution that the odds belie.
Failing that, succeeding generations might need to consider emigrating to Mars, as there won't be much left to enjoy any closer to home.