[hackable_sand]

You can change sex

And people can be born intersex

Your data is wrong

[Saline9515]

The fact that some people can be born with 6 fingers doesn't mean that saying "a human hand has 5 fingers" is generally false.

[duskdozer]

It also means you can't use the generalization "a human hand has 5 fingers" to then say that "therefore because your hands have 6 fingers, you are not a human"

[Saline9515]

I the sense of what OP did say, it would be more "grafting a sixth finger doesn't mean that you are not human anymore".

Just like taking meat from your arm to create new genitals doesn't make you a man, biologically (psychologically it may be different).