Ever been to the fridge and discovered that there’s a milk carton there but with only the puniest dribble of cow-juice left in it, not even enough to soften a thimble of tea?

You, my friend, are a victim of that scourge of society, the curse of the polite amount.

Basically, the polite amount is the smallest amount of foodstuff a person can leave without actually finishing it off completely. This usually applies to foodstuffs consumed between people or in a social context.

It could be a splash of milk.
A scrape of butter.
A single, solitary bar snack.

You’ve all been there: sitting in a pub with friends, a solo crisp or dry-roasted peanut gazing up in a lonely way from the bowl or the splayed silver bag innards on the table, with your friends stealing guilty/frustrated/longing glances at it because no matter how hungry, no-one wants to be The Finisher: the one who polishes it off.

You know it when you see it:

• A single chocolate, left in the box.
• A sad biscuit at the bottom of a gaping tin.
• A dice-sized chunk of cheddar.
• A solo slice of bread. And it’s the heel.
• Not enough coffee to make a difference.
• A portion of rice that would make UN emergency rations look generous.
• Half a teaspoon of pesto.
• The last spring roll when there’s an even number of you and the dish contained five.
• Twenty-eight cornflakes, huddled at the bottom of the promising cavern of their box, on top of the fridge.

The issue of polite amounts arises from one of two sources:

a) generosity of spirit and
b) laziness and/or cheapness.

Despite being seemingly opposed, both motivations can create the same results: crushing disappointment and seemingly endless pettiness.

The generosity of spirit argument usually occurs when someone doesn’t want to finish something off. You know the situation - you want to leave something for the next person, because being The Finisher would be bad: it would seem inconsiderate of others.

The laziness/cheapness argument reads the same: you don’t want to finish something off, you want to leave something for the next person, because being The Finisher would be bad - only THIS time, it’s driven by the reasoning that it would be bad because the person who finishes a thing needs to wash it up OR buy a replacement. So you justify in your head that it’s OK not to throw away the cereal box (or even buy more cereal) because there was still some left, even if you’d have to be one of The Borrowers to truly appreciate it.

This leads to stubborn standoffs which can involve flatmates (or couples, even) dividing a remaining portion of pasta salad in half, then half again, then again, until there is only a single farfalle, a cube of chopped pepper and a cherry tomato left, in order to avoid having to wash the bowl it was contained in - and all the while ready with a defence of innocence which insists that “there was still some left and I didn’t know if you wanted any.”

So after years of experiencing this in shared flats and with friends when out, my flatmate C and I when living in Bolivia together had only one house rule: No Polite Amounts. Evah.

This meant that if you made a cup of tea, and there wasn’t much milk left (enough for one cup, but not for two), then according to the law, it was better to use it up completely than to put a pathetic ooze back in the fridge which might fool the next tea-hunter into thinking that there would be a nice cuppa in hand soon enough, only to discover at the point of insertion that the amount left in the carton wasn’t in fact enough to flavour even the tiniest shot of tea. By simply finishing it off completely - even if that meant overmilky tea - the disappointment of the one who follows could be easily avoided.

The rule was surprisingly effective: it made us more considerate, and made the fridge much more manageable. It lessened the number of spats in the house. And it provided a useful primer for later life, and one which I encourage you to adopt.

So I say: down with polite amounts. Say no to the curse of leaving a little bit. Finish up with pride - and then do your fucking duty and replace it or wash up, if that’s what’s required.

It’s a small price to pay for a happy social or domestic life, I’m telling you.