A better idea that a lot of people have is the you should never get married in a month that has a Wednesday in it.

A similar idea is that one should enjoy a beer on days of week that end with 'y'.

days that start with a T, like tuesday, thursday, thaturday thunday, today, and tomorrow.

:(

I believe it's the opposite (only marry in r-months).

But unlike English, in Polish r-months are randomishly distributed over the year:

• March (marzec)

• June (czerwiec)

• August (sierpień)

• September (wrzesień)

• October (październik)

• December (grudzień)

… so it's not like either rule would make any sense.

I too have heard the positive version of the rule. The randomness might be intentional, so as to make one wait a random but not too large number of months, perhaps to discourage marrying in haste or as an artificial (but reasonable) constraint on planning to increase the perceived value of the event.

Perhaps that's also why there are two variants, so that it works whichever month you are currently in!

In Italy you shouldn't get married (or leave for a trip) on Tuesdays and Fridays.

Possibly because those are the days associated with Mars and Venus in romance languages.

In English, Tuesday is named for Tiw and Friday for Frig. Monday for the moon, Sunday for the sun, Wednesday for Woden (more commonly known by his Norse name, Odin), and Thursday for Thunor/Thunder (Norse name: Thor).

When your ancestors met mine, they decided Tiw was the equivalent of Mars, Woden of Mercury, Thunor of Jupiter, and Frig of Venus, and hence the correspondence.

https://en.m.wikipedia.org/wiki/Interpretatio_graeca#Interpr...

Sadly, English mythology is now much less well known than Roman, so most people aren’t even aware of these etymologies.

> Sadly, English mythology is now much less well known than Roman, so most people aren’t even aware of these etymologies

In my experience most people aren’t even aware of any etymologies. Or even the word itself.

Spain: "en martes ni te cases ni te embarques" (on Tuesday, don't get married and don't board a ship)

you shouldn't start a business/project either ("...né si dà principio all'arte")

I thought Mars is the god of marriage, and Venus is the god of venturing. It's right there in the name.

According to the OED, the Latin root of “marriage” is of uncertain origin. As far as I’m aware, there’s no known connection to Mars.

No, Mars is the god of war (and the archetype of masculine) and Venus the god of love (archetype of feminine).