[oilinki (OP)]

My friend has been calling me as 'old uncle' and I have been calling him as 'young kid' for couple of decades. This is because I have been born 3 days before him.

But things get more complicated, when we take in to account that I have been born 2 weeks before my due date. He was born close to his predicted date.

Could I claim that I'm actually younger than him as my first cell division occurred later compared to his and therefore my cells are younger than his?

[PmbPhy]

My friend has been calling me as 'old uncle' and I have been calling him as 'young kid' for couple of decades. This is because I have been born 3 days before him.

But things get more complicated, when we take in to account that I have been born 2 weeks before my due date. He was born close to his predicted date.

Could I claim that I'm actually younger than him as my first cell division occurred later compared to his and therefore my cells are younger than his?

This is merely semantics. There's no scientific basis to any answer given since what a persons age is determined merely by how we define it.

[oilinki (OP)]

Thanks for your reply!

It might be semantics, but it's actually a real question from real life. It would be nice to hear different opinions from different backgrounds.

For me personally, I want to be the younger one and be able to call my friend as 'old uncle'.
(the younger/older labels work much better in Finnish).

I would have placed this on Iq Nobel section, if there had been one. The questions which make you laugh, but then make you think.

[PmbPhy]

Thanks for your reply!

It might be semantics, but it's actually a real question from real life.

I understand that. Semantics is the branch of linguistics and logic concerned with meaning. So this is a question on the meaning of the word age. That's all I meant. If you define age as the length of time from birth then it has one value. If you measure age from the length of time from when the person was predicted to be born then he has another value. Who's to say which is right and wrong?

[oilinki (OP)]

I know, There might never be a correct answer. While you take the question forward in a good way, your questions opens up even more questions. That's something I like as well.

But as I'm determined (not seriously) to proof to my friend that I'm actually younger than he is, I need some solid theories, which I can cherrypick for my own proof.

At the same time it's very interesting to hear both the philosophical as well as biological ideas, how old we actually are? Should we define our birthdates as simply one of the events of our life, which begun when our first individual cell was formed?

[unfortunately this idea might bring the abortion folks to the discussion, that was not my intention. Then again, should we really restrict our free ideas by the way some extremist wish to define those? I think not.]

[PmbPhy]

But as I'm determined (not seriously) to proof to my friend that I'm actually younger than he is, I need some solid theories, which I can cherrypick for my own proof.

(BTW - the correct phrase is "to prove" not "to proof"). Your best bet is to say that you've been on this earth longer than he has since you were conceived before he was and that quite literally makes you older. How's that?    Lol!!

[Colin2B]

But things get more complicated, when we take in to account that I have been born 2 weeks before my due date. He was born close to his predicted date.

Could I claim that I'm actually younger than him as my first cell division occurred later compared to his and therefore my cells are younger than his?

He probably won't accept it unless you have proof of conception date. Some parents keep track and record it in their Baby Book, some can't recall the event, others might want to forget!

[alancalverd]

Due dates and predicted dates are moderately informed guesswork, based in most cases on the mother's last reported menstruation. Since menstrual periods are individual and variable, and the period of fertility can be a few days either side of peak, the least unreliable way to establish your date of conception is to ask your mother, and if your parents had a reasonably friendly relationship, she probably won't be too sure either. 

Fortunately the law takes a pragmatic attitude: your legal age is defined by your birthday.