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Can a Living Creature Be as Big as a Galaxy?

nautil.us

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Re: Can a Living Creature Be as Big as a Galaxy?

#121

Post by fattire »

delecti wrote: post #118
Consultant32452 wrote: post #117

Earlier quoted context omitted.

There are more bacterial cells in your body than there are human cells. Where exactly do you draw the line between what constitutes "you."

A zoo is still a zoo if there aren't any animals in it, but it wouldn't stay in business very long. No matter how important the animals are to the long-term viability of the zoo, they are not the zoo. My gut bacteria may be vital to my survival, but they are not me. I don't find placing that line to be difficult at all.

> A zoo is still a zoo if there aren't any animals in it

Is it? Identity is an interesting thing. To use a commonly-cited example-- if I swap out the muffler of my car and toss the original in the backyard, I think most would say I am still driving the same car. If I do the same with the front left tire, it's still essentially my car. Even if replace all four tires, same. But what if I swap one part a day with a replacement, after a while I'll have all my original car parts in the backyard-- and am in effect driving a car made of totally new parts, but is this still the same car? If not, when would you no longer say it's the same car? And, if I assemble the collection of gradually discarded parts sitting in the back yard into another car-- now what? Which is my car? The thing I'm driving or the car made of the old parts? Or are they both the same car?

Am I really the same person I was when I was 10 ...or 10 months? What is the "me"-ness, or are we talking about a different person? Where's the line...

Or... when Captain Kirk uses the transporter-- his molecules are disintegrated, and then a copy of him gets assembled on some planet (using local materials I believe)... So is "he" transported, or is he being killed and replaced with an exact copy? (I think this question made its way to a Breaking Bad episode)

Anyhoo. Is a zoo without animals in it still a zoo? I dunno.

Re: Can a Living Creature Be as Big as a Galaxy?

#122

Post by JorgeGT »

fattire wrote: post #121
delecti wrote: post #118

Earlier quoted context omitted.

A zoo is still a zoo if there aren't any animals in it, but it wouldn't stay in business very long. No matter how important the animals are to the long-term viability of the zoo, they are not the zoo. My gut bacteria may be vital to my survival, but they are not me. I don't find placing that line to be difficult at all.

> A zoo is still a zoo if there aren't any animals in it Is it? Identity is an interesting thing. To use a commonly-cited example-- if I swap out the muffler of my car and toss the original in the backyard, I think most would say I am still driving the same car. If I do the same with the front left tire, it's still essentially my car. Even if replace all four tires, same. But what if I swap one part a day with a repl…

It's an age old question indeed, the example you cited has been recorded from at least the first century: https://en.wikipedia.org/wiki/Ship_of_Theseus

Re: Can a Living Creature Be as Big as a Galaxy?

#124

Post by olegkikin »

andars wrote: post #63
olegkikin wrote: post #48

Earlier quoted context omitted.

You're presuming the speed of light is the hard limit. Whereas we know for a fact faster movement is possible - the space-time itself was expanding faster.

You have some misunderstandings about the expansion of the universe. I would recommend reading http://www.preposterousuniverse.com/blog/2015/10/13/the-univ...

No, it's you who gets incorrect information from some random blogs.

The size of the observable universe: ~93 billion light-years

Time since the big bang: ~13.7 billion years.

http://curious.astro.cornell.edu/about-us/104-the-universe/c...

https://phys.org/news/2015-02-fast-universe.html

Re: Can a Living Creature Be as Big as a Galaxy?

#125

Post by [deleted] »

diminish wrote: post #100
stareatgoats wrote: post #88

The question is not correctly formed: what we really want to know is if there are life-like beings that could operate on a totally different scale than ours (both time and size wise, including viruses and whales here). Self centered thinking, i.e. restricting our inquiry to only include protein-based lifeforms or other qualities required on our scale obviously prevents us from having the required open minded mindset.

states, companies, religious communities, planets as whole ecosystems can all be construed as "single being"s.

[deleted]

Re: Can a Living Creature Be as Big as a Galaxy?

#126

Post by chongli »

knome wrote: post #120
delecti wrote: post #118

Earlier quoted context omitted.

A zoo is still a zoo if there aren't any animals in it, but it wouldn't stay in business very long. No matter how important the animals are to the long-term viability of the zoo, they are not the zoo. My gut bacteria may be vital to my survival, but they are not me. I don't find placing that line to be difficult at all.

The only part of the flesh which is "you" is the nervous system. Everything else can be hacked off or replaced without a loss of identity.

So if somebody has a limb amputation, losing a lot of nerves, are they a different person? Is somebody a different person when they're drunk? I've heard both of these thrown around colloquially. It's not obvious or straightforward to answer.

You could imagine a Ship of Theseus style replacement of all the neurons in your head with artificial ones. At what point would you stop being you?

Re: Can a Living Creature Be as Big as a Galaxy?

#127

Post by Koshkin »

seszett wrote: post #105
Koshkin wrote: post #74

Earlier quoted context omitted.

There are a few things that are wrong with Wikipedia's (re)definition of life; one thing I would like to mention is that what is missing from it is that a "living being" cannot exist outside of a pretty rich (and sufficiently dense) material environment, which 'space' as such is not. Incidentally, a galaxy-size dense environment (and the creature itself) would collapse into a bunch of stars and black holes "in no tim…

> a "living being" cannot exist outside of a pretty rich (and sufficiently dense) material environment What makes you say that, though? I don't see any reason for it. Some ethereal galaxy-scale lifeform might be thinking as well that "life cannot exist in the extremely hot, hyperdense environment of a planet" for example. This is pure speculation from your part.

You may be right about ethereal lifeforms, but real ones need to eat, breathe, etc.; they are also subject to the laws of thermodynamics: they need energy, and also in order to maintain low entropy inside they must increase the entropy of the environment - which would be hard if there was no environment to speak of.

Re: Can a Living Creature Be as Big as a Galaxy?

#128

Post by Consultant32452 »

delecti wrote: post #118
Consultant32452 wrote: post #117

Earlier quoted context omitted.

There are more bacterial cells in your body than there are human cells. Where exactly do you draw the line between what constitutes "you."

A zoo is still a zoo if there aren't any animals in it, but it wouldn't stay in business very long. No matter how important the animals are to the long-term viability of the zoo, they are not the zoo. My gut bacteria may be vital to my survival, but they are not me. I don't find placing that line to be difficult at all.

Are the dead cells you're carrying around like your hair "you?" What about food? At what point exactly in the digestion process does it cease to be something else and become part of "you?" Is your urine and fecal matter that's still within your body "you?" How about the oxygen in your blood? Is that you? Saliva? How about tears? When to tears stop being you and become something else?

Re: Can a Living Creature Be as Big as a Galaxy?

#130

Post by wruza »

knome wrote: post #120
delecti wrote: post #118

Earlier quoted context omitted.

A zoo is still a zoo if there aren't any animals in it, but it wouldn't stay in business very long. No matter how important the animals are to the long-term viability of the zoo, they are not the zoo. My gut bacteria may be vital to my survival, but they are not me. I don't find placing that line to be difficult at all.

The only part of the flesh which is "you" is the nervous system. Everything else can be hacked off or replaced without a loss of identity.

Without instant loss of identity, I would add. It is widely known how semipathological states are cause of character, mood, life style, etc. There is no strict line between 'you' and your body (and internal-external environment); cutting or hacking non-utility parts of it will change you in short period of time, compared to original, as it happens with less radical change of climate, country, job, gender, food.
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