Well, Viruses also don’t produce their own energy and they don’t grow, so my point still stands.
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But human red blood cells don’t grow or produce their own energy either, so would they not be considered living?
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Oh come on
Yeah, that’s the problem. There’s tons of grey area - the science isn’t as clearly cut as a lot of people think it is.
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The issue here is that the concept of “alive” is a manmade construct, and so the discussion is really about what that term should mean. The general consensus, and the one that makes the most sense, is that viruses are just floating packets of genes, but not themselves alive. Having genes does not constitute life; certain processes/functions do.
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There’s not going to be a definite answer to this, only different takes coming from different definition. Doesn’t mean the discussion is pointless though.
Also your red blood cell razor only works if I consider red blood cells alive, which I don’t. That’s like saying a Hormone is alive. It’s merely a part of a living organism.
The issue is that it not being alive would mean it isn’t a cell.
We really need to figure out what qualifies as “living” before we can find out if a virus is living, because you can’t classify something into a group if you don’t know what qualifies for being in said group.
Only if your definition of cell includes alive, which it doesn’t. Cells usually qualify for “living” but it isn’t part of their definition.
Right, now we’re getting to the core of the problem. Finding a definition for life is, as it turns out, incredibly difficult because you always end up including too much or too little. There’s that little checklist we used to learn in school where we count it as alive if “enough” criteria are met. Just to find out that one’s hotly contested in academia as well, apparently.
The difference between opinions usually comes down to how the criteria are weighted. I personally don’t put too much weight on reproduction while I strongly value maintaining Homeostasis and having its own energy household.
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This is my checklist for a living thing
-
It produces its own energy
-
It can reproduce
-
It can grow and or change
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It is made of cells
-
It has metabolism
That’s it for my list so what do you guys think?
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I’d add aforementioned Homeostasis and some other contested but still overall helpful points. We can rank how important they are later.
- It can maintain Homeostasis (keep its own body at living conditions)
- It can react to it’s environment.
A few more indicators that help but are definitely not required imo
- independent movement
- evolves over generations
- it is compartmentalised into something along the lines of a cell
Oops, here I wanted to stay neutral and I already discredited some of the criteria.
You can scratch that point. Producing energy is a required part of having a Metabolism so it’s already included in there.
Yeah. That makes sense.
Here is the revised checklist!
Required criteria
- It can reproduce
- It can grow and or change
- It is made of cells
- It has and can maintain metabolism
- It can react to it’s environment
Non-required criteria
- Independant movement
- evolves over generations
- It is compartmentalised into something along the lines of a cell
I believe the most generally accepted definition of life is that an organism needs to be able to reproduce, grow, metabolize, and react to stimuli - the smallest unit able to accomplish all of those things are unicellular organisms.
So cold blooded animals aren’t actually alive? They require the outside environment to regulate their internal environment.
This is rendered redundant as a criterion at this point in time, because Cell Theory already states that all animal and plant life are comprised of cells.
The revised revised checklist
Required criteria
-
It can reproduce
-
It can grow and or change
-
It has and can maintain metabolism
-
It can react to it’s environment
Non-required criteria
- Independant movement
- evolves over generations
- It is compartmentalised into something along the lines of a cell
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This was a part of the not required criteria meaning that it means that a thing is alive but it doesn’t need to maintain it to be alive.
The issue here is that we have no real definition and any definition we come up with will inevitably be flawed.
Which is false. It doesn’t need to maintain its own homeostasis.
Additionally, the entire definition of a criteria is that it is required - “non-required criteria” is self-negating.
yeah, now we need to see what criteria viruses meet, which may be a problem, because viruses are different from each other.
Viruses meet none of these criteria, except possibly being able to react to stimuli. But now we’ve come full circle, because the argument is whether or not failing to meet those criteria is sufficient to classify it as not being alive - whether or not those criteria are a sufficient definition for life.
Again, the science is far from clear cut, and we’ve been talking in circles for a while.
So back to the original question - by this definition, that an organism must be able to metabolize, grow, reproduce, and respond to stimuli, viruses are not, in fact, alive. That does not negate the possibility that they may be classified as living by future definitions of life, but according to current science, viruses are not alive.
Yes. if they don’t meet any of these criteria then they are not “alive”. Though, “life” is a man-made concept (just like time) that does not have a clear definition, so how can you classify something when you don’t know what the classification is? You can’t, and with everything that has been said above, we have come to a conclusion that viruses, in fact, are not alive.
EDIT: What questions do you have about this?
I’m confused because I feel you simply restated what I said 
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