Many people have mistaken Cinderella to be a tale of romance against adversity. You may remember the tale to be about a poor, working girl who finally got a shot at living the high life and finding her prince charming. Curiously, all of this nonsense about fairy godmothers, pumpkins and the like were overlooked by our younger, less skeptical selves.

Upon closer inspection, we can derive some truths whilst eradicate some myths about the tale. That she was a working girl is true. That she went out to a ball is also true. That she met some nice fellow but conscientiously left at midnight is all true! The rest, however, is absolute rubbish.

You see, the fact is that Cinderella was a young professional who understood that although going out to balls and meeting princes can be jolly good fun and all that… she had to get up for work the next morning. The truth is that Cinderella taught us nothing about romance or adversity.

Instead, she taught us the importance of trade-offs and exponential time discounting.

Cinderella, like any of us, went out drinking on the town on a weeknight. The difference between you and her, is that she realised that it made perfect economic sense to go home at midnight.

It’s quite simple, really. Beyond a certain point in time the utility that you gain from staying out and partying doesn’t sufficiently compensate the disutility that you get from losing that time in which you could have been sleeping. Put differently, the opportunity cost of staying out and drinking is the sleep that you could be getting otherwise. For anyone that has had to work the next day, you know… it’s rarely worth it.

The crappy sleep, the headache, the fatigue, the hating on peeps on the train, the hating in general. And for what? Typically for conversation that deteriorated into talking about celebrities’ haircuts – invariably in a slurred, drawled and unintelligible manner. I mean, have you ever looked back at a debaucherous weeknight and thought – “man when we stuffed our underpants with ice cream at 3am it was TOTALLY WORTH IT”?

I suspect that the lower life forms of you lot might beg to differ. But I’m not particularly interested in your opinion. Nor would be Cinderella.

But to be clear, Cinderella and I aren’t only looking at one side of the equation. We’re well aware that going out and partying IS a lot of fun, it’s just that on weeknights you have an extra constraint to consider. After all, we’re only looking out for your true ‘time value’.

You see, going out and drinking is a logarithmic function of utility. This means that the increase in your happiness (utility) is propelled greatly by the amount of time you spend out on the turps. However, it is also a diminishing function after a certain point. This means that your level of utility ‘plateaus’ after a certain point in the night. Maybe the 15th beer didn’t really add all that much more value than the 14th, for example.

Now when you’re out on a weeknight, there’s another function that you need to consider. It’s a negative logarithmic function which represents the utility that you lose by not getting to bed. Because in this case, waking up the next morning’s totally gonna be a drag.

Basically this function gets off to a slow start, which pretty much tells us that you’re not really losing all that much utility to start with. But then it accelerates after a certain point in the night. Maybe after about 4am, when you start to think… “Why am I still awake? And why’s there a circus clown following me?”

What Cinderella was interested in was the optimal point at which these functions intersect. Cinderella helped us to find that point, and I took the liberty to sketch a graph to illustrate her message for you.

And so is revealed the truth behind Cinderella: the micro economist.

No pumpkins. Just economics.