glass half full or empty

How full is the food glass?

Many believe humanity continues inextricable progress. Others that we career towards a cliff of resource scarcity. Is the glass half full or half-empty? There is a way to find out…

Food production for humanity has grown exponentially over the last 100 years reaching unprecedented levels. It will continue to grow for decades and must persist at these levels for at least another 100 years for humanity to avoid catastrophe.

Now depending on your view of the glass, this is a half-full or half-empty situation.

So many customers is a huge economic opportunity for those who can grow food profitably or assist those that do. There is serious money to be made. 

Plenty of people means huge amounts of brainpower and inspiration to solve whatever food production and diet problems come our way, not to mention the opportunity to build and sell technologies.

Clearly a half-full glass.

Servicing so many customers requires a huge amount of resources for the production and distribution of food that uses up natural capital and leaves a trail of external impacts on the environment. 

Soon enough, the eating and drinking of fossil fuels will slow as the once-only fossil fuel pulse ends.

Food supply chains are vulnerable to shocks from local to global scale leaving an impression of fragility rather than stability and at risk of disruption from economics as well as nature. They also fail to deliver adequate nutrition to a third of the global population.

This glass is emptying fast.

Is the food production glass half-full or half-empty?

Both options have merit. 

The glass of human development has been brimming over for centuries and ever faster since the capture of energy from fossil fuels—success that we have converted into more people. Technology helps with any number of challenges and the dominant capitalist model of finance provides more than enough incentive for technologies to flourish. 

However, the requirement for 22 trillion kilocalories a day of nutritious food is daunting. There were a mere 5 million people alive at the time agriculture was invented coincident with the last glacial maximum. Since then, it has been warming, and we now have 8 billion people_two orders of magnitude more—with most of the usable agricultural land already under production, the oceans overfished, and limits to key nutrients.

So how do we choose? Half-full or half empty.

Here is a cautionary tale that might help your choice…

The Lily Pad Puzzle

Imagine a small pond that has clear blue water reflecting the summer sky.

In the centre of the pond are two Lily pads, the emergent leaves of an aquatic plant, floating safely on the surface of the water, curled up edges keeping the surface of the leaf dry.

On one Lily pad is a green frog.

The frog is hard to pick out on the green pad but a yellow stripe on its back gives it away.

Chance happens that a week later you pass by the same pond and stop to admire the scene. Sure enough, the frog is still there, only you notice that there are now four Lily pads; the number of leaves has doubled. In a week the frog has gained surface real estate.

A week later you happen to pass by the pond again and even before you spot the frog you see that there are now eight Lily pads. These aquatic plants are quite prolific.

You have to go away for a while and forget the frog and his growing number of Lily pads. A few months pass. Delighted to return home you saunter by the pond again. The first thing you see is that the pond is now mostly green as half of it is covered with Lily pads and rather less of the blue sky is reflected in the water.

Sure enough, the frog is still sitting proudly in the middle.

The puzzle question is this.

How many more weeks until the pond is completely covered with Lily pads and the frog can hop to shore without getting wet?

Photo by Orkhan Farmanli on Unsplash

The problem with a half

Half is awkward for a finite resource. 

It is the point where just before or just after there is either more or less than there was before. A kind of tipping point.

Before one half there is plenty left in the tank. After one half there is always less. 

And this is the reality for natural capital. In principle, much of what nature provides is renewable making it hard to consume more than half. Only the current global demand is unprecedented and we are over half of just about all the critical resources and services humans rely on.

This brings us back to Lily pads and the answer to the puzzle.

How many more weeks until the pond is completely covered with Lily pads and the frog can hop to shore without getting wet?


Hero image modified from photo by Joseph Greve on Unsplash


Mark is an ecology nerd who was cursed with an entrepreneurial gene and a big picture view making him a rare beast, uncomfortable in the ivory towers and the disconnected silos of the public service. Despite this he has made it through a 40+ year career as a scientist and for some unknown reason still likes to read scientific papers.

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