Woah. What a thread.
I'm a visual thinker and I've always seen things like this as and not other, and popped onto a Venn diagram. I may be thinking more simply about this than required but sometimes that's the best way.
And in primary school science it's characteristics of living things. I couldn't remember if subset is a term in Venns so I went off to check.
It doesn't appear to be so. It seems that the term to describe the area where two characteristics are shared is union and the area is called the intersection.
From Wikipedia:
The combined region of sets A and B is called the unionn^ of A and B, denoted by A ∪ B. The union in this case contains all living creatures that are either two-legged or that can fly (or both).
The region in both A and B, where the two sets overlap, is called the intersectionn of A and B, denoted by A ∩ B. For example, the intersection of the two sets is not empty, because there are points that represent creatures that are in both^ the orange and blue circles.
I've always seen this as where you are trying to show that women with another protected characteristic are doubly disadvantaged. So being a woman and severely disabled leaves her more vulnerable to sexual abuse in a care home. Being a woman and black means you are subject to the extra layer that comes with racism and misogyny.
The Venn groups would be A) BAME (men and women) and B) women. The union would be BAME women.
So you can't put TW into an intersection with women on one side and ?? Men on the other unless you use gender stereotypes. So it doesn't work.
I tried to get my head around set (subset) theory applied in this way and it doesn't seem to work (using scientific criteria) but I need to look at it again and at the quote upthread.
So again a situation where semantics and scientific and this time mathematical criteria have been skewed / used and then misled (if TW are W.)