The rules of public grooming: Rudy Giuliani shaves in a restaurant. Should you?

Name: Public grooming.

Age: Pre-human.

Appearance: Rudy Giuliani shaving himself in an airport restaurant.

Why on earth would you put an image like that into my mind? I didn’t. Rudy Giuliani did, by shaving himself in an airport restaurant.

Wait, this happened? Unfortunately, yes. A man called Nick Weiss filmed it happening on Sunday in the Delta One lounge at JFK airport.

The former New York City mayor was shaving himself at the table? Yes, shortly after eating a lobster bisque, followed by a plate of brownies.

Is this sort of thing allowed now? That depends. Do you really want your personal grooming icon to be Rudy Giuliani?

He’s a very successful man. Yes, a successful man who once made a speech with hair dye streaming down his head, and is reportedly a fairly prolific public farter.

Maybe he had a good excuse. Perhaps there weren’t any suitable facilities nearby? According to Weiss, the shaving happened a few steps away from a “really nice” bathroom.

OK, fine. But can we really say that an airport restaurant counts as a normal restaurant? For relaxed, leisurely dining? No. But for spraying thousands of bits of your own hair all over the table and floor? Yes, yes it absolutely does.

This feels sexist. Why are women allowed to do their makeup at a table, but men can’t shave? Well, strictly speaking, they aren’t. As etiquette bible the Emily Post Institute states: “It’s OK to quickly apply lipstick at the table if you’re with close friends or relatives in a non-business situation”, but it’s definitely not recommended outside this context.

Why can’t men shave, then? Oh, I don’t know, maybe it’s because applying lipstick doesn’t shoot microscopic hair clippings all over an area where people have to eat?

So that’s the public grooming rule: don’t leave a mess? Now you’re getting it. Applying moisturiser good, clipping your nails bad. That sort of thing.

Smoothing your eyebrows good, plucking your eyebrows bad. That’s it! Let’s try some more. Applying lip balm?

Good. Correct. Flossing your teeth?

Bad. Really bad! Unacceptably bad. Never floss your teeth in public.

This is actually really useful. Can we do gym changing room etiquette next? No, I’m sorry, we cannot.

Why? Is it too complicated? Listen, I’ve just spent all this time teaching you not to shave in a restaurant. Educating you on the subtleties of blow-drying your pubic hair in front of people may take years.

Do say: “Can I have the bill, please?”

Don’t say: “And a great big tub of hair removal cream while you’re at it?”