Hacker News Reader

Comment by fiatjaf | Hacker News Reader

I get mad at people who think sons of first-cousins are second-cousins all the time -- and, frankly, almost everyone I know think this way.

I'm glad you linked to this Wikipedia article that proves I'm not mad into thinking there is a simple logic pattern that can be applied to cousinship.

However, this "once removed" notation is crazy. Why not second-uncle for parents of second-cousins and so on?

View on HN

Pardon me for my ignorance, but wouldn't sons of first cousins be second cousins?

Language quirk :) The son of my first cousin is my first cousin once removed. My son and my cousin's son are second cousins.

Ah, I read "sons of first cousins" as "two people who are first cousins to each other each have a son". "A son of a first cousin" would be much less ambiguous. In fact, even knowing what you meant, I have a hard time reading the meaning you intended to convey.

Another clearer way to phrase it would be "sons of my first cousin are not my second cousins".

Actually the term "second cousin" does not have a concrete meaning. It can mean a true second cousin, or it can also mean a generation removed from a first cousin. The "once removed" terminology was introduced to compensate for this ambiguity.

No! Stop the removed madness!

Generally the "1st/2nd" bit denotes how many generations up you have to go to find a common ancestor, and "removed" is how many generations removed the other person is from that generation.

You are, to your your first cousin's child, who is your first cousin once-removed, a second cousin once-removed.

yes. the wording and the fact that other people seemed to agree with the op made me spend way too much time on this.

He must be referring to one's own first cousin's children. Not the children of two first cousins.

You can call them anything you like, I'm just saying that you shouldn't.

That's what I use.

2nd uncle, 2nd grand aunt

Fun fact: in Russian a first cousin is a 2nd Brother/Sister, a 2nd cousin is a 3rd Brother/Sister and so on.

That makes a lot of sense! The distinction between sibling and nth cousin is basically arbitrary. (Although obviously there is logic in making the distinction as well as in omitting it.)

Arbitrary? You have the same parents with sibling; with cousin you share only one of the two pairs of grandparents.

Actually that's often but not always true -

    brother b1 and sister s1 from family 1, with parents g1
    brother b2 and sister s2 from family 2, with parents g2
    s1 has child x with b2 - x has grandparents g1, g2
    s2 has child y with b1 - y has grandparents g1, g2

x and y are cousins, and also share the same 2 pairs of grandparents :-)

Those are "double first cousins". I even have some triple cousins in my tree, where three siblings from one family married three siblings from another family.

It can get even more fun!

If instead of two brothers marrying two sisters, you have two brothers marrying two first cousins, like so...

    b1 and b2 are brothers
    c1 and c2 are first cousins
    b1 and c1 marry and have child x
    b2 and c2 marry and have child y

... then x and y are both first and second cousins (and their children are second + third cousins, etc).

Agreed: in the case of siblings you share all ancestors; with cousins only some. In that way the distinction makes sense. The other way to look at it though is that with siblings your common ancestor is one generation up. With first cousins, it's two. With second, it's three. So it's the same thing, just a matter of degree.

No, you don't. You don't call a son of your first-cousin your second-cousin. You call him a second nephew I think.

First cousin once removed.

https://upload.wikimedia.org/wikipedia/commons/4/4c/Cousin_t...

No, stop that removed madness!

Thank you for being sane.

Russians are decent people, it seems. Is the 2nd-uncle terminology widespread in Russia too?

Also good because it means you are your own 0th brother which makes sense. In the western version you are your own -1st cousin :(

Worse even, the "once removed" notation has no notion of direction, so it's inherently ambiguous. I'm also pretty sure that less half of the people I hear using it know what it means (or tries to mean).

There's an app for that!

https://www.microsoft.com/en-us/store/apps/cousinosity/9nblg...

This got me confused. You actually mean people who confuse "second niece" (i.e. your cousin's son) with "second cousin". Is that usage common in english? The daughters of cousins are second cousins,no?

Isn't the term "uncle" relatively recent? I recall Hamlet referring to his father's brother as his cousin.

You must be very old.

You are hitting the borders where logic and common usage meet.

I am actually surprised that descriptive grammar holds up so well to logic. (There's no a priori reason why descriptive grammar, that describes common usage of language, actually is as mostly compressible to simple rules as it is.)

If there's a clearer and more specific way to speak about something, we should try to use it.

Design of language is a constant trade-off, between ease of remembering, compression (ie giving shorter ways to express more common concepts), fault-tolerance, desire of the speaker to look clever, fashion, ...

And all of us work on the evolution of language every day.

That's how we've always done it.

* Brother of father is uncle. Son of uncle is cousin. Son of son of uncle is second cousin.

* Brother of grandfather is great-uncle. Son of great-uncle is second cousin.

That's exactly what you shouldn't be doing.

Edit: Nvm. I am more confused than I thought.

I've always wondered about this one:

My father's first-cousin-once-removed is what to me?

That depends on which direction the cousin is removed. If a generation above your father, it is your first cousin twice removed. If a generation below, it is your second cousin.

Your second cousin if you share the same great-grandparents.

Edit: Ugh, this gets confusing. I was mistaken. I'd originally included the once-removed, but that appears to be incorrect. Or I'm still mistaken. :)

A first cousin once-removed signifies one person's grandparent is the other's great-grandparent.

Perhaps this cousin chart would help: https://en.m.wikipedia.org/wiki/Cousin#Relationship_charts

Just plot yourself and the cousin-in-question by where your shared nth-grandparent lies.

Depends on the direction removed?

I think, if your father's cousin-once-removed is a generation below him, then he/she is your first-cousin. While a generate above you father would signal first-cousin-twice-removed...

Thoughts?

In the first case he/she would be your second cousin, not first.

http://www.wolframalpha.com/input/?i=father%27s+first+cousin...

First cousin twice removed, apparently.

You are a (1,0)-child to your father (who is a (0,1)-parent to you). Your father is either (2,3)-cousin or (3,2)-cousin to the other person. It is ambiguous from the terminology. So you are either (3,3)-cousin or (4,2)-cousin to them. That is second cousin for the former and first cousin twice removed for the latter.

You get mad? Really? Why?

Reply on news.ycombinator.com