Today, October the 5th 2015, England finally caught up with the rest of the UK in trying to encourage a nationwide experiment in positive constraints: No Plastic Bags. From today, all shops and chains with more than 250 employees (in total, not per shop) will have to charge at least 5p for a plastic bag.
On the face of it, this is an excellent initiative and not a moment too soon. Plastic bags are phenomenally damaging to our natural environment. They are not biodegradable and litter the countryside and pollute our rivers for, not decades, but hundreds of years after they have been discarded.
Plastic bags are also totally unnecessary. The number of times I am automatically handed a plastic bag when I’m only buying a banana and a block of cheese is a constant source of annoyance to me. Even when I do need some sort of conveyance to transport my produce from shop to home, I’d far rather be given something I can either use again or that I can throw in the compost, like a paper bag or cardboard box.
You knew there was going to be a “but”, didn’t you?
While I applaud any attempt to encourage us to consume less plastic, I know from experience that you can’t force people to adopt a positive constraint. In fact, that’s a contradiction in terms. The “positive” refers to the free agency of the person affected. This, effectively, is a government-imposed negative constraint – albeit one that has very noble ambitions. And negative constraints don’t work very well in the long term.
It is far more effective to freely decide yourself to stop using plastic bags than it is to allow the pain and inconvenience of a 5p charge make that decision for you.
Fascinatingly, if you take a close look at the statistics, there may already be some evidence to back up my worries. Much has been made of the 78.2% reduction in plastic bag usage in Wales since they introduced the 5p plastic bag charge in 2012. However, if you look back through the data, plastic bag usage has increased every year since the charge, from 62 million in 2012 to 73 million in 2013 and 77 million last year (you can delve deeper on the BBC here).
This is, of course, still a huge drop from the 273 million plastic bags that were used in 2011, but it does make me worry about the long-term efficacy of such a scheme. Why? Because a negative constraint (or “stick”) approach like this provides only an extrinsic motivation for No Plastic Bags. Extrinsic motivation, for example when we are motivated by money, fame or public approval, is linked with lower levels of compliance and lower satisfaction when we achieve the object of the motivation.
What we need are postive constraints, where the motivation for the behavioural change comes from within each of us, so that the motivation is intrinsic. This is how our new No Plastic Bag habits will last, not just until we forget the pain of the 5p charge, but for the rest of our lives.
(But still: No Plastic Bags, yay!)