Sunday, May 23, 2010

I made the mess; I'll clean it up?

The myth of reversibility

I made the mess, I'll clean it up.
I opened the door, I'll shut it.
I tangled the fairy lights, I'll unknot them.
I pulled apart the radio, I'll reassemble it.

I scrambled the eggs, I'll unscramble them.
I ate the omelette, I'll regurgitate it.
I burned the masterpiece, I'll repaint it.
I chopped off my leg with a chainsaw, I'll sew it back on.

We depleted the aquifer, we'll recharge it.
We burned the oil, we'll regenerate it.
We destabilised the climate, we'll restore it.
We pushed the species into extinction, we'll resurrect it.
Not all actions are equally reversible. Some, like opening and closing a door, can be easily "undone" with similar effort to the original deed. But many actions lead to a significantly lower level of order (i.e. a gain in entropy), and consequently are significantly more difficult to reverse. While microsurgery may indeed be able to reattach an amputated body part, this is far more difficult than causing the initial injury, and there will still be scars.

Yet the idea that "because human actions have caused our various ecological crises therefore human actions must also be able to be solve them" is a common theme in popular environmental discourse. Even some scholars repeat this unfortunate meme.

Despite this frequently expressed hope, some deeds have effects which are very difficult, if not impossible, to undo. The inequality of ease between actions that increase order and those that decrease order is one implication of the second law of thermodynamics.

Prevention is cheaper than cure
In other words, prevention is better than cure. At least, it requires less effort in most instances. In fact, an EU report on the costs of biodiversity loss due out later this year is expected to put the costs of prevention at somewhere between one tenth and one hundredth the costs of remedy.

We underestimate our ability to cause damage (a topic for a future post) and overestimate our ability to fix it. This is not a recipe for inaction, paralysed for fear of doing harm, but a reason for taking greater care in what we do. Humanity has a marvellous ability to adapt to new and challenging circumstances, but we are also right to cherish prudence.


byron smith said...

Yes, I realise that the second law of thermodynamics only applies to closed systems and that the earth is not a closed system as it receives sunlight. Nevertheless, the observation that "things tend to fall apart more easily than they are put together" is not unrelated to this law.

Darren Allen said...

Its all my fault!