What is IT that makes Us, Us?

We are our memories. What else shapes our personalities and makes us unique if not things that happened to us in the past? Otherwise, we're generally pretty much the same.

'Every year about 98% of the atoms in your body are replaced'. Where did you hear that extra medium?

Probably not every year, but I'm sure 98% of the atoms in my body are going to be completely different at some point. It's not really relevant.

I just like facts rufio, that's why I asked it :wink:

You are your memories. The memories of what we have experienced, all the things you have learned are the only things that matter. Memories inform your personality, your behavior and your identity.

(By the way I don't think the 98% number is ever true. There is much more than 2% of the atoms in your body that will stay with you for life. But I agree with rufio that it doesn't matter.)

I don't think there the concept of a "soul" is helpful in this discussion. I am not saying that there is one, or isn't one, but we can have an identity without a soul even with changing atoms.

Of course in any discussion about "soul" the concept of soul must be defined. If you define it as a collection of memories, I will agree.

Rick,
Here's one source(scroll a bit down on this page and you'll see it):
http://www.chemistry.mcmaster.ca/~chem1aa3/note/kinetics/kinetics.htm

Its a fairly commonly accepted scientific fact. Try going to google and entering 98% atoms in human body replaced each year and you will find many supporting sources.

Thanks for the link, I'm convinced.

I read an article several years back about a neurologist studying the "self".

He had found that people suffering from injuries to a certain part of their brain would, in fact, lose themselves. They would switch religions or political parties or friends or everything while still retaining their memories. They would act different and dress different and just BE different.

They didn't really understand the mechanics of this, just like they don't really understand most of the brain's mechanics, but it surely seems as if they'd found the "self".

Hell, most of it's just water anyway.

I'd say the structure of the brain. When people succumb to dementia, we say, "So and so is not his/herself."

More famously, there was the guy Robert (?) Gage a ways back who took a railroad spike through a frontal lobe and his personality changed completely. One of his coworkers described the shift from a friendly, honest, conscientious guy to a complete bastard thus: "Gage was no longer Gage."

Gosh, I didn't know the science police were out today. To those who so easily dismissed the "98% of atoms replaced every year" statement, here are a few sources:

http://www.chemistry.mcmaster.ca/~chem1aa3/note/kinetics/kinetics.htm

http://www.ryanandfriends.1hwy.com/facts.html

http://www.planetc1.com/cgi-bin/n/search.cgi?category=1&keyword=Bittman&page=53

http://www.rosezone.com/booksales/im_203/image134-JPEG.html

http://www.femalemuscle.com/library/weekly/aa110899.htm

Anyway, that wasn't really the point...are you saying that there are a few atoms that hang around forever, that keep you, you?

It appears that we have 2 camps thus far:
1. We are our memories.
2. Our self is created by a certain part of our brains.

1. We are our memories.
Thats pretty good. But the thing that comes to mind there, is: What about when I was born, then? I was nothing? Or maybe I was nothing in the womb, at some point? And then I slowly became this common thread thing as I gained memories? What about people that have amnesia, but apparently still have the same personalities, etc.?

2. Our self is created by a certain part of our brains.
Boomerang & patiodog, this seems to be really getting at something. The brain injury changing the self, etc., seems to be really getting at something.
Still the question I have there is: Every atom in the brain will be replaced within a few years. Lets take an uninjured brain. Whatever it is in there is completely replaced within a few years. Yet you are still the same person. Yet this "self-creating" portion of your brain has been completely replaced. What is the common thread that is keeping you the same, even though this portion of the brain has been totally replaced?

I'm just asking questions here, I really enjoy learning from everyone on this board...

Sorry that this piece of pseudo-scientific trivium is distracting from an philosophical question that is inherently interesting. But as a science geek, I have got to answer this.

There is absolutely no way that this 98% figure each year is true. Just think about it. This means that there isn't even 3% of your body that is the same from one year to the next?

How many atoms in your bones do you think are changed each year? You bones are pretty solid and themselves consist of more than 3% of your body. My teeth haven't grown since I was 7 or 8. That my fillings are staying put is evidence that there is not much change.

Skins cells and stomach linings do change and I am sure that there are a large percentage of atoms that are changed.

But there are certainly much more than 2% of the atoms of the body-- eyes, brain, bones that don't change year by year.

As I always say:

"Everthing that is true is on the internet,
but not everything that is on the internet is true."

ebrown,

Okay. Lets assume the 98% per year isn't true. Lets say it takes 8 years to replace all your atoms. Yet you are still the same person.

You are right. It wasn't really the 98% I wanted to discuss, it was how could all your atoms be replaced, yet you still be the same person, etc.

Anyway, can we move past the 98% question & move onto: how can you be the same person after all your atoms have been replaced?

ebrown,

I don't know if the claim is true or not, but there is a big difference between replacing atoms and replacing cells. Functional proteins (i.e., enzymes) are replaced at a pretty rapid rate; mostly this consists of taking the subunits apart and putting them back together, but new material must get incorporated at times, as well. The tiny amount of us that is DNA should contain some pretty old elements, as it is replicated in a semi-conservative fashion -- though even old strands are disrupted and replaced through repair mechanisms. The nonliving matrices of bones and teeth may or may not have been included in the estimates. If not, though, that leaves living cells, which are highly dynamic. Though you are stuck with a neuron for life, the material that makes up the neuron -- membrane, proteins, et al. -- is constantly recycled.




The structure, however, remains the same. If you change the hoses on your car, it's still the same car, doing the same things; functionally, the car has not changed.

patio,

Point taken. Still, I'm not quite seeing the answer of what makes us, us? Are you saying the structure of these portions of our brains affects who we are?

Some people have memories even of when they were in the womb. Memories don't always stay with us, but they help shape your personality as you grow up, until they are lost or replaced. I don't think you could say that there is any instance in your life in which you don't have memories, except during the period of time in the womb in which you don't have enough of a brain to have memories - in which period you probably couldn't be considered a human yet. No amnesia is total, and people may very well be affected by memories that they can no longer remember, and carry those effects through long after the memories have faded. Hence the effectiveness of hypnosis and all of frued's crapola.

I do think there are periods of our early life that are beyond what we commonly call memory.

But they do make us who we are - how we were treated, were we well fed, loved, cared for -- or not. Those experiences might not be memory but they are part of our "selves".

I like your car analogy, patiodog.

In early life we don't have identity in any sense of the world. Infants can't tell where "self" ends and the world begins. Newborns believe that they are the only thing in the Universe.

In these periods boomerang refers to, an infant is developing memories that will inform its indentity and even the roots of personality.

So it looks like maybe its a combination. We are our memories. But there may be a particular part of our brain that sort of stores, organizes, etc. our memories, and helps to regulate and create our "selves."

So, still, begging the question:

What is it that enables us to remain the same person, even though all the atoms have been replaced in this portion of the brain. What is it, outside of atoms & cells, that somehow maintains our identity. Memories? What are memories? (thats another thread) Somehow memories, then, must be transferred from old atoms to new atoms at some point. Now this is interesting. Memories & our identity being transmitted from old atoms to new atoms. Atoms mixing together, somehow communicating to one another, to ensure that our identity & memories remain somewhat consistent over time. Atoms telling each other: "Hey, I see you're new around here. I'm about ready to be replaced. Here, take my part of what this dude is all about. Got it? Good. I'm outta here." Interesting.