What is the karma of a tumbler or a pot?
To hold water or some other liquid, right?
There's a glass lying in your room for last 10 years and you have never seen any water in it.
Is it still a tumbler? +

When you bought it, your intention was to use it for drinking water/ tea/ coffee from it but now you are doing any of that.
Is it still a tumbler?
Let's say, instead of pouring water in it, you started keeping pens in it, you'll probably give it a new name such as 'pen-holder'+

But that could create confusion as there might be already be a class of products 'pen-holders'.
If a huge enough no. of tumbler have no contact with water and start holding pens instead, tumblers would become a sub class of 'pen-holders' +

But as long as there's a sizeable no. of tumblers into which water is poured or as long as people drink water in tumblers only, the tumbler- water association will remain.
And at the root of it is the prevalent idea that tumbler is something that is used for holding water. +

The question one is alluding to is if the class tumbler came first or its use? When a factory makes steel tumblers, didn't it make with the assumption that it will used for drinking water?
It's same as the question we encounter so often on Twitter: Jaati is by birth or karma?+

If we go to the very first tumbler, it's clear that the class came first. Even before anyone had drunk water from any tumbler, even before a single tumbler was produced, it was given a name and a function was assigned to it. So clearly, the class ( or caste) came first +

However, future production of tumblers will also depend on actual no. of users using it to drink water, If no. is small , the tumbler- water association breaks.
This is broadly the essence of Jaati debates.
This thread was instigated by a lecture of @govardhanmath maharaja.