What is Life?

[dkv]

What is alive according to the Neuro Science students?

Regards,

DKV

[bascule]

Life denotes all entities which have descended from the progenotes, the common ancestors of everything which is presently alive.

 

In a grander scheme of things, life denotes any naturally occuring mechanisms which garner extropy through gradual yet progressive incremental process of self-replication.

 

Replicators which don't evolve (e.g. fire) aren't alive

[dkv]

Life denotes all entities which have descended from the progenotes, the common ancestors of everything which is presently alive.

dkv:Well sir the defintion carries the question ...

 

In a grander scheme of things, life denotes any naturally occuring mechanisms which garner extropy through gradual yet progressive incremental process of self-replication.

Replicators which don't evolve (e.g. fire) aren't alive

rep:so the speed of replication is a criteria..some physical states other than fire also replicate for example Pearl stones on the sea shore which look alike.

the process is very different.But they gradually come into existence and they indeed evolve from one material into other.

Any comments,

[bascule]

Well sir the defintion carries the question ...

 

You're missing the point. Life is all one giant chemical chain reaction. Anything which isn't a product of the initial reaction (likely to be a variadic autocatalyst) isn't "alive"

[dkv]

Chemical Reaction which we choose to accept as life.There are other forms of chemical reaction as well with short life span.

I feel the behavioural semantics should be the only criteria for defining life as scientists are trying to achieve the same in other fields of knowledge .. for example robots with sufficient complexity can tomorrow be called alive..

Nano technology allows self replication.

But we do not want our definitions to change as we somehow still believe that something should be missing in it to call it alive.

What is it ?

Thats my question.

[ecoli]

Life denotes all entities which have descended from the progenotes' date=' the common ancestors of everything which is presently alive.

 

In a grander scheme of things, life denotes any naturally occuring mechanisms which garner extropy through gradual yet progressive incremental process of self-replication.

 

Replicators which don't evolve (e.g. fire) aren't alive[/quote']

 

that's not a bad definition, except you're excluding potential extraterristrial life.

[bascule]

that's not a bad definition, except you're excluding potential extraterristrial life.

 

That's what the second definition I gave was meant to encompass

[dkv]

But the definition was not sufficiently correct..

[ashennell]

I feel the behavioural semantics should be the only criteria for defining life as scientists are trying to achieve the same in other fields of knowledge .. for example robots with sufficient complexity can tomorrow be called alive..

 

I think there is a difference between something exhibiting intelligent/motivated behaviour and being alive.

 

I would go with something like Bascules second definition. I'm not completely happy with it but I'm not sure how I would improve it either.

 

By the way, i don't think 'extropy' denotes the opposite of entropy. I've never seen it used in this context and I think it has some other wierd meaning anyway.

[Scarygeorge]

So, where does consciousness fit into all this?

[theMaharajah]

Life is what you make of it

 

as in:

"people who post on SFN have little to no life"

or

"theMaharajah has an awesome life"

 

meer examples, they hold little to no truth

[sabbath]

So, where does consciousness fit into all this?

 

Consciousness is inherent in the higher beings, but that's too crude. Let's say consciousness is inherent in creatures/species with advance and developed ganglia. But one doesn't have to be conscious of life to be alive.

 

Biologically, an organism is alive when it's organs/organelles or its general anatomy functions to enable the organism to carry out the processes of life, ex respiration, metabolism etc.

 

Am I even making sense?

 

If AI computers come into being, they would, technically be alive I suppose. Not organically, but mechanically.

[sabbath]

The conventional definition according to google states that for an organism to be alive it must have: organization, undergo metabolism, reproduce, undergo growth, respond to stimuli, and adapt to its environment.

 

Yet life is said to be a multifaceted concept.

[bombus]

Just the plain old 2nd Law of Thermodynamics doin' its stuff:

 

Please see below:

 

by SCOTT SAMPSON

Chief Curator, Utah Museum of Natural History; Associate Professor Department of Geology and Geophysics, University of Utah;

 

The truly dangerous ideas in science tend to be those that threaten the collective ego of humanity and knock us further off our pedestal of centrality. The Copernican Revolution abruptly dislodged humans from the center of the universe. The Darwinian Revolution yanked Homo sapiens from the pinnacle of life. Today another menacing revolution sits at the horizon of knowledge, patiently awaiting broad realization by the same egotistical species.

 

The dangerous idea is this: the purpose of life is to disperse energy.

Many of us are at least somewhat familiar with the second law of thermodynamics, the unwavering propensity of energy to disperse and, in doing so, transition from high quality to low quality forms. More generally, as stated by ecologist Eric Schneider, "nature abhors a gradient," where a gradient is simply a difference over a distance — for example, in temperature or pressure. Open physical systems — including those of the atmosphere, hydrosphere, and geosphere — all embody this law, being driven by the dispersal of energy, particularly the flow of heat, continually attempting to achieve equilibrium. Phenomena as diverse as lithospheric plate motions, the northward flow of the Gulf Stream, and occurrence of deadly hurricanes are all examples of second law manifestations.

 

There is growing evidence that life, the biosphere, is no different. It has often been said the life's complexity contravenes the second law, indicating the work either of a deity or some unknown natural process, depending on one's bias. Yet the evolution of life and the dynamics of ecosystems obey the second law mandate, functioning in large part to dissipate energy. They do so not by burning brightly and disappearing, like a fire torching a forest, but through stable metabolic cycles that store chemical energy and continually reduce the solar gradient. Photosynthetic plants, bacteria, and algae capture energy from the sun and form the core of all food webs.

 

Virtually all organisms, including humans, are, in a real sense, sunlight transmogrified, temporary waypoints in the flow of energy. Ecological succession, viewed from a thermodynamic perspective, is a process that maximizes the capture and degradation of energy. Similarly, the tendency for life to become more complex over the past 3.5 billion years (as well as the overall increase in biomass and organismal diversity through time) is not due simply to natural selection, as most evolutionists still argue, but also to nature's "efforts" to grab more and more of the sun's flow. The slow burn that characterizes life enables ecological systems to persist over deep time, changing in response to external and internal perturbations.

 

Ecology has been summarized by the pithy statement, "energy flows, matter cycles. " Yet this maxim applies equally to complex systems in the non-living world; indeed it literally unites the biosphere with the physical realm. More and more, it appears that complex, cycling, swirling systems of matter have a natural tendency to emerge in the face of energy gradients. This recurrent phenomenon may even have been the driving force behind life's origins.

 

This idea is not new, and is certainly not mine. Nobel laureate Erwin Schrödinger was one of the first to articulate the hypothesis, as part of his famous "What is Life" lectures in Dublin in 1943. More recently, Jeffrey Wicken, Harold Morowitz, Eric Schneider and others have taken this concept considerably further, buoyed by results from a range of studies, particularly within ecology. Schneider and Dorian Sagan provide an excellent summary of this hypothesis in their recent book, "Into the Cool".

 

The concept of life as energy flow, once fully digested, is profound. Just as Darwin fundamentally connected humans to the non-human world, a thermodynamic perspective connects life inextricably to the non-living world. This dangerous idea, once broadly distributed and understood, is likely to provoke reaction from many sectors, including religion and science. The wondrous diversity and complexity of life through time, far from being the product of intelligent design, is a natural phenomenon intimately linked to the physical realm of energy flow.

 

Moreover, evolution is not driven by the machinations of selfish genes propagating themselves through countless millennia. Rather, ecology and evolution together operate as a highly successful, extremely persistent means of reducing the gradient generated by our nearest star. In my view, evolutionary theory (the process, not the fact of evolution!) and biology generally are headed for a major overhaul once investigators fully comprehend the notion that the complex systems of earth, air, water, and life are not only interconnected, but interdependent, cycling matter in order to maintain the flow of energy.

 

Although this statement addresses only naturalistic function and is mute with regard to spiritual meaning, it is likely to have deep effects outside of science. In particular, broad understanding of life's role in dispersing energy has great potential to help humans reconnect both to nature and to planet's physical systems at a key moment in our species' history.

[sunspot]

If you look how the sun's energy is stored within life, via photosythesis, it is the reduction of hydrogen. When life burns the stored energy within the hydrogen it ends up, if oxygen is present, as water. This thermal chemical gradient is within the range of hydrogen bonding. This path makes sense since the sun is also mostly hydrogen.

 

All the important biomaterials of life like DNA, RNA and proteins, etc., have hydrogen bonding energyies within the range of this primary solar induce hydrogen gradient of life. The life molecules evolve by spreading laterally to help fine tune the hydrogen energy gradient, creating more effecient lifeforms that can store and process more and more solar energy. The human brain is at the top of the heap burning continuously at about 100 watts, triggering the muscles to burn even more.

[Cloud]

Life is the ability to relay an electrical impulse. my right?

[Prime-Evil]

In the greastest sense, all that exists is life.

We are all connected.

[ecoli]

Life is the ability to relay an electrical impulse. my right?

 

So, does that mean my house is alive, because it has an entire system of electrical impulses and signals?

[Cloud]

So, does that mean my house is alive, because it has an entire system of electrical impulses and signals?

 

That response was so inevitable, I don't know what to say.

[Prime-Evil]

Isn't it somewhat ironic that a creationist from 800 years ago was more able to accept stars and planets and rocks and air and water and fire, and even abstract ideas like death, as a fellow living creature, than most of we scientists are able to today. All generalizations fail, but are still useful.

 

Canticle of Brother Sun

 

Most High, all-powerful, all-good Lord,

All praise is Yours, all glory, all honour and all blessings.

To you alone, Most High, do they belong,

and no mortal lips are worthy to pronounce Your Name.

 

Praised be You my Lord with all Your creatures,

especially Sir Brother Sun,

Who is the day through whom You give us light.

And he is beautiful and radiant with great splendour,

Of You Most High, he bears the likeness.

 

Praised be You, my Lord, through Sister Moon and the stars,

In the heavens you have made them bright, precious and fair.

 

Praised be You, my Lord, through Brothers Wind and Air,

And fair and stormy, all weather's moods,

by which You cherish all that You have made.

 

Praised be You my Lord through Sister Water,

So useful, humble, precious and pure.

 

Praised be You my Lord through Brother Fire,

through whom You light the night

and he is beautiful and playful and robust and strong.

 

Praised be You my Lord through our Sister,

Mother Earth

who sustains and governs us,

producing varied fruits with coloured flowers and herbs.

 

Praise be You my Lord through those who grant pardon

for love of You and bear sickness and trial.

Blessed are those who endure in peace,

By You Most High, they will be crowned.

 

Praised be You, my Lord through Sister Death,

from whom no-one living can escape.

Woe to those who die in mortal sin!

Blessed are they She finds doing Your Will.

No second death can do them harm.

 

Praise and bless my Lord and give Him thanks,

And serve Him with great humility.

[ecoli]

That response was so[/b'] inevitable, I don't know what to say.

 

how about an 'oops'

[SkepticLance]

Life on Earth has three qualities that can be incorporated into a definition.

 

1. Replication or reproduction.

2. Ability to evolve.

3. Based on a complex system of organic chemicals.

 

Number 3 is needed to exclude certain computer programs.

 

Now, there may be life off Earth which does not fit this definition. However, a definition does not have to include anything that is currently pure speculation.

[ecoli]

that's not too bad for life on Earth, excpet that the term 'complex' is kind of subjective.

[WillTheNewf]

concsciousness is our perception of everything

[ashennell]

Life on Earth has three qualities that can be incorporated into a definition.

 

1. Replication or reproduction.

2. Ability to evolve.

3. Based on a complex system of organic chemicals.

 

Number 3 is needed to exclude certain computer programs.

 

number 2 would seem to imply number 1 which would make it redundant.

 

if number three is included to rule out computer programs then I assume it is not actually included to define life. It seems like you start with the assuption that computer programs are not alive (im not saying this is wrong) and then add a term to rule them out. surely we should start with a definition and then decide what examples fit.

 

It is interesting that many of the definitions include evolution. Doesn't evolution require a population to work on?