What's the smallest thing that can be alive?

[Philocrat]

'Logic' is not the culprit here, but rather, the set of axioms and laws that belong to physics.


In a nutshell, if we want phenomenal consciousness to 'land,' we must provide it with a more suitable theoretical 'perch.' In the meantime, we must recognize the crucial difference between access consciousness (a functional system of global control, 'global workspace,' etc.) and phenomenal consciousness (subjective experience, qualia, etc.). Working within the standard physical paradigm, you could make a case that a system must model itself if it is to achieve the former, but to approach the latter you must provide significantly more theoretical motivation.

I think this distinction is well-taken and understood. But as I have pointed it out eslewhere on PF, the former may outlast the latter, for the latter may very well be structurally re-engineered out of place. It may vanish into the former, thus rendering the human conscious existence fully public. And like a goldfish in a glass of water, there will be no place for visual information of all kinds to hide!

 

[Math Is Hard]

I came across this web page, and I thought this person (an oceanographer) had some good things to say on the subject of what constitutes living matter
http://www.oceansonline.com/lifeprops.htm

His key points:
Living matter is organized into complex structures based on organic molecules.
Living matter maintains some type of homeostasis.
Living matter grows and develops.
Living matter reproduces and passes on genetic material as a blueprint for growth and subsequent reproduction
Living matter acquires matter and energy from the external environment and converts it into different forms.
Living matter responds to stimuli from the environment.
Living matter evolves.

 

[Chronos]

How about DNA? DNA = alive, No DNA = not alive.

 

[Gerinski]

Just for discussion, these are the properties listed by Paul Davies in his book "the fifth miracle" for considering something as alive:

- Autonomy
- Reproduction
- Metabolism
- Nutrition
- Complexity
- Organization
- Growth and development
- Information content
- Hardware / Software entanglement
- Permanence and change

He summarizes all of them in just 2 broad items:

1. Metabolism
2. Reproduction

 

[Math Is Hard]

How about DNA? DNA = alive, No DNA = not alive.

Would a computer program that emulates DNA instructions count?

 

[Math Is Hard]

Hardware / Software entanglement

Could you briefly tell me what this means? Thanks.

 

[Math Is Hard]

Something else I find a little troubling - if we consider a brain dead person on life-support, or perhaps a baby that's born without a functioning brain and is kept alive on life support, for a more extreme example... I am not sure if either is categorizable as alive. Or am I back to the parasite scenario again? The living thing is supported by a machine host as well as the environment.

 

[Chronos]

Would a computer program that emulates DNA instructions count?

Only molecular DNA need apply .