http://en.wikipedia.org/wiki/Virus#Life_properties

Quote :

"Life properties Opinions differ on whether viruses are a form of life, or organic structures that interact with living organisms. They have been described as "organisms at the edge of life",[53] since they resemble organisms in that they possess genes and evolve by natural selection,[54] and reproduce by creating multiple copies of themselves through self-assembly. Although they have genes, they do not have a cellular structure, which is often seen as the basic unit of life. Viruses do not have their own metabolism, and require a host cell to make new products. They therefore cannot naturally reproduce outside a host cell[55] —although bacterial species such as rickettsia and chlamydia are considered living organisms despite the same limitation.[56][57] Accepted forms of life use cell division to reproduce, whereas viruses spontaneously assemble within cells. They differ from autonomous growth of crystals as they inherit genetic mutations while being subject to natural selection. Virus self-assembly within host cells has implications for the study of the origin of life, as it lends further credence to the hypothesis that life could have started as self-assembling organic molecules.[1]"

http://en.wikipedia.org/wiki/Life#Definitions

Quote :

"Definitions It is still a challenge for scientists and philosophers to define life in unequivocal terms.[11][12][13] Defining life is difficult —in part— because life is a process, not a pure substance.[14] Any definition must be sufficiently broad to encompass all life with which we are familiar, and it should be sufficiently general that, with it, scientists would not miss life that may be fundamentally different from earthly life.[15] Biology Since there is no unequivocal definition of life, the current understanding is descriptive, where life is a characteristic of organisms that exhibit all or most of the following phenomena:[14][16][17] 1. Homeostasis: Regulation of the internal environment to maintain a constant state; for example, electrolyte concentration or sweating to reduce temperature. 2. Organization: Being structurally composed of one or more cells, which are the basic units of life. 3. Metabolism: Transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism). Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life. 4. Growth: Maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter. 5. Adaptation: The ability to change over a period of time in response to the environment. This ability is fundamental to the process of evolution and is determined by the organism's heredity as well as the composition of metabolized substances, and external factors present. 6. Response to stimuli: A response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms. A response is often expressed by motion, for example, the leaves of a plant turning toward the sun (phototropism) and by chemotaxis. 7. Reproduction: The ability to produce new individual organisms, either asexually from a single parent organism, or sexually from two parent organisms. Proposed To reflect the minimum phenomena required, some have proposed other biological definitions of life: * Living things are systems that tend to respond to changes in their environment, and inside themselves, in such a way as to promote their own continuation.[17] * A network of inferior negative feedbacks (regulatory mechanisms) subordinated to a superior positive feedback (potential of expansion, reproduction).[18] * A systemic definition of life is that living things are self-organizing and autopoietic (self-producing). Variations of this definition include Stuart Kauffman's definition as an autonomous agent or a multi-agent system capable of reproducing itself or themselves, and of completing at least one thermodynamic work cycle.[19] * Life is a self-sustained chemical system capable of undergoing Darwinian evolution.[20] * Things with the capacity for metabolism and motion.[14] "

With all the pro-choice/life discussions going on, I though it'd be interesting to have this conversation too. Hard to define what counts as a living person without defining living.

7/14/2010 3:45:36 PM

I don't think this issue is relevant at all for abortion. What matters is whether what we're killing is "properly human" or "morally relevant".

In other words: we kill living things all the time. This is not always unethical (or at least, it's not always unjustified; we have needs). The real question of interest in the abortion debate is not whether you're killing something or not (it seems quite clear you are); the question of interest is whether you're killing a human in any meaningful sense or not.

7/14/2010 3:47:35 PM

Perhaps a more interesting thread would be to ask what distinguishes the human animal from other animals in terms of qualifying for person-hood. Other than that obvious spark of the divine known as the soul.

7/14/2010 3:51:42 PM

I'd have to say mastery of recursive language then, I guess.

7/14/2010 3:53:37 PM

You kill "life" when you brush your teeth.

7/14/2010 3:56:04 PM

Is this page 7 of prolife vs. prochoice or what?

delete, suspend.

7/14/2010 3:57:28 PM

No, this is page 7: http://brentroad.com/message_topic.aspx?topic=597966&page=7

7/14/2010 4:00:37 PM

^^^ You certainly do. Jesus fuck, that has nothing to do with anything.

Quote :

"I don't think this issue is relevant at all for abortion. What matters is whether what we're killing is "properly human" or "morally relevant". In other words: we kill living things all the time. This is not always unethical (or at least, it's not always unjustified; we have needs). The real question of interest in the abortion debate is not whether you're killing something or not (it seems quite clear you are); the question of interest is whether you're killing a human in any meaningful sense or not."

Exactly, with one caveat, in that this discussion may be relevant as a first step towards defining the things you mention.

7/14/2010 4:06:07 PM

The OP asked for my definition of life. I gave it to him. Jesus fuck.

7/14/2010 4:07:00 PM

Quote :

"Exactly, with one caveat, in that this discussion may be relevant as a first step towards defining the things you mention."

We can all agree that human beings are, at the very least, living. The question that abortion debates (should) turn on is the question of moral agency; what is a moral agent, and what isn't? What sorts of human systems have moral agency and which ones don't?

7/14/2010 4:11:36 PM

^^Either that's the most piss-poor "definition of life" I've ever seen, or that was directed at the abortion debate rather than the OP, and now you're trying to avoid owning up to it. Your pick.

In either case, it's an utterly irrelevant comment.

[Edited on July 14, 2010 at 4:13 PM. Reason : ^ You'll have to translate the philosophy verbiage. I'm a mechanical engineer.]

7/14/2010 4:11:57 PM

I mean to say what sorts of things are morally relevant? What "counts" in a moral sense and what doesn't?

If somebody handed you a vat of human skin grown in a lab and said "please dispose of this", you probably wouldn't consider it a moral issue. This is a clear case of a human system that has no moral relevance (the bucket of skin, that is). Our goal, philosophically, is to draw a reasonably clear dividing line between human systems that get moral relevance and those that don't.

7/14/2010 4:14:57 PM

OK, I'm with you. I'll have to bow out temporarily...mostly because I need to hit the gym and go to bed, and also partially because I'll need to think about that one before making my input.

7/14/2010 4:17:42 PM