7 ms·

This sentence captured my mind: > Scientists still debate whether viruses are alive—they can’t replicate independent of a host cell’s molecules—but there are e

• Tagbert 3y ago
  People like definitions that have clearly defined boundaries but biology is not like that. There can be a messy continuum between is and is not. Things can match a definition strongly by some measures but miss some that are critical to how other things meet the definition. At best, a definition is a constellation of semi-related characteristic where some organism meet some subset and other meet another subset, but there isn’t a 100% match and may not even be an overlap.
  • yowzadave 3y ago
    > There can be a messy continuum between is and is not. Exactly--concepts like "life" were invented long before we had an inkling of what viruses were...is it surprising that it's not a perfect abstraction for what we find in reality?
  • PeterStuer 3y ago
    I think people have no qualms about fuzzy boundaries or continuities. The problem arises when those get subsequently mapped onto discrete sets with wildly different consequences. My work in computational ontology led me to believe people are fast to come to a conceptual joint agreement in a given model when the outcome is not consequential, but find it nearly impossible to settle when there are strong implications attached to a labeling. Language only works between people that ultimatly want to agree.
    • vjk800 3y ago
      If labeling has fuzzy boundaries, perhaps it shouldn't have strong implications. If it does, the boundary cases behave chaotically, which is usually not acceptable behaviour. I mean, if the labels have no consequences, what is the point of labeling in the first place? Organizing everything in the world into neat boxes feels so early 20th century to me. Back when we still thought that human reasoning can be applied to achieve a complete understanding of the world and everything in it. Putting things into boxes is a coping mechanism for the feeling of chaos; people do it because it makes them feel good, not because it actually reflects how things are.
      • InSteady 3y ago
        >If labeling has fuzzy boundaries, perhaps it shouldn't have strong implications. Well, it's tricky because labelling is so useful (oftentimes crucial for communication purposes), but we would be hamstringing ourselves if we either a. held off on labeling things with fuzzy boundaries altogether or b. refused to entertain possibilities with strong implications because a labelled phenomenon has fuzzy boundaries. Best to remember that labels are useful but with very important limitations. Ultimately, when we get out to the edge of our understanding the boundaries will always be fuzzy, at least until a breakthrough (and sometimes long after). Whenever you are at a boundary, continually remind yourself that the label is less important than communication and exploration of what actually appears to be going on. Are viruses alive? This is a very interesting question to try and answer from different angles, but arriving on a definitive "yes or no" here is not at all the most important thing about viruses to be worrying about.
      • PeterStuer 3y ago
        We label because we need to compress reality before we can reason and make sense. Is this a limitation of human intelligence? Sure, but I would hypothesise it is even more fundamental. Irreducible complexity can only be observed and reacted to, it takes away the proactive. So we make do with reduced models that are definetly wrong, but sometimes usefull.
• zdragnar 3y ago
  In a way, a virus is not too far off from a complex prion. Simple single cell organisms aren't too far off from complex viruses. There's a line of thought that metabolism is the defining feature of biological life, and viruses do not have any metabolic activity of their own. This is essentially the only real distinguishing characteristic that holds true between viruses and organisms. Once a virus has a host cell, however, it uses metabolic events to do its thing. That use of those events to drive its own reproduction is very life-like, and is very unlike a prion. In terms of behavior, it really is more like life than not. It uses metabolism, even if it doesn't innately perform glycolysis like everything else. The "are viruses alive" is really more a medical philosophy question than a practical one.
  • Terr_ 3y ago
    And then on the other side of prions, you get things like asking whether self-catalyzing crystal formations are alive.
  • andrewflnr 3y ago
    In what way is a virus remotely like a prion? Both the structure and function of the parts are completely different. Just because a virus interacts with a metabolism doesn't mean it's closer to having one of its own. That's like saying humans use gasoline combustion for our biology because we drive cars instead of walking sometimes. You're not wrong that whether viruses are alive is not a very practical question, but none of the rest of your post meaningfully addresses it either way.
    • deleted 3y ago
      [deleted]
    • chasil 3y ago
      A viral capsid is certainly an evolutionary benefit, but the disease known as "scrapie" astonishingly seems to be able to survive without one for long durations. We are quite lucky that nothing like that targets humans so effectively.
      • 3y ago
• scoofy 3y ago
  My background is philosophy of language. The vagaries of definitions are exactly how many get communication backwards. It’s jut important to remember that language is effectively just pointing at things, and that the words we use are effectively arbitrary. The distinctions in taxonomy should be reflected by the language, and we should very much not try to conform our taxonomy to our existing terms… beyond, say, shorthand.
  • colordrops 3y ago
    This is clear to many of us with no formal training in language.
    • scoofy 3y ago
      I completely agree, and wouldn’t suggest otherwise. I’m mainly referring to the concept of platonic ideals, which seem to be at least somewhat instinctual.
      • colordrops 3y ago
        Yes, that was my original understanding of your meaning. There are other experiences and traditions as well that illuminate this way of thinking.
  • staplers 3y ago
    we should very much not try to conform our taxonomy to our existing terms I see this stunting imagination everywhere. Economics, science, nature, etc. Humans generally feel they've "captured" knowledge with a brief overview and disdain any messiness that might allow that knowledge "to escape".
    • patcon 3y ago
      Some humans are curious to be exploratory of knowledge that "escapes" these classifications, as you say :) this is, in some definition, the criteria of an artist of sorts. Maybe artistic minds are just scientists of another cloth, investigating the features of linguistic creatures that escape the boundaries that other (more "particular") types of minds create and impose
• _heimdall 3y ago
  [flagged]
  • tjpnz 3y ago
    >Koch's Postulates where redefined and then abandoned entirely by virologists as they couldn't find a way to apply them to viruses. Koch's Postulates have since found new life among conspiracy nuts as indisputable proof that viruses aren't real.
    • Geezus_42 3y ago
      Great...
    • _heimdall 3y ago
      I don't think the question is whether viruses are real, the question is whether scientific studies have yet to show transmission of infection that leads to disease. There isn't a scientific definition for "real" that I'm aware of. Do you know of any studies that have isolated a virus, or a virus plus host cells, and successfully introduced those into a novel population to reproduce disease? All I've ever managed to find are epidemiological studies after an assumed viral outbreak, but I really am interested to see a more controlled study that helps prove a more direct link.
      • yankoff 3y ago
        Are you questioning whether viruses can infect organisms or whether they can cause disease?
        • anonymouskimmer 3y ago
          In general this line of argument is questioning how we can know that a particular virus causes a particular disease. It ignores decades of technological improvements developed toward actual viral bulkup, purification, and infection. Is it easy to know that a particular virus causes a particular disease? Not always, particularly if the disease syndrome is complex. Is it possible to link particular viruses to particular diseases? Definitely. For the more straightforward diseases it's even relatively straightforward to show that a particular virus causes that particular disease, with enough work.
• anonymouskimmer 3y ago
  A virus usually encodes for, and definitely utilizes, many processes of living things. Part of the breakdown here is recognizing independent life requiring only a nutrient and energy source, and various consortia (e.g. can you say that a mitochondrion is alive without the host cell, and vice versa). Basically, as mentioned by another commenter, the fact that "life" started out as a Platonic ideal that's being sussed out. I'd say just change it to an adjective entirely and don't bother with a categorical noun.
  • usrusr 3y ago
    "nutrient and energy source" is an interesting perspective: we certainly can't live off radiation (or heat, or electricity, or whatever one might consider as direct energy input) plus all the atoms contained in a lifetime worth of food arranged in simple monogamous molecules. We are no less dependent on other organisms arranging atoms into molecules our bodies can use as fuel and building blocks than a virus is dependent on a host cell for reproduction. I suppose that we can't really want a definition of life that excludes everything that isn't a plant?
    • anonymouskimmer 3y ago
      As you state, the carbohydrates, fats, and proteins in our food sources function as energy sources. Photons are great for plants, but comparatively high-energy chemical bonds are fine, too.
• epgui 3y ago
  Something is getting lost in translation here, because scientists are not literally "debating" whether viruses are alive. Scientists "discuss" the boundary between alive and not, which is an interesting question because it doesn't have a super clear and obvious answer. It becomes more a question of semantics and ontology than anything else. What's really happening is that the words "alive" and "not alive" have outlived their usefulness: we need to think about things differently, and use better words, to fully capture how the world works. That's the discussion, and yes it's similar to what's happening with words like intelligence and consciousness in relation to AI.
• anileated 3y ago
  > nothing could end that debate Oh yeah, it could. If AI is textbook-defined technically “sentient” then that is perfectly enough to put an end to unethical abuses of sentient beings. (Imagine what that will do to the industry.) It doesn’t matter if people still debate it. People still debate race supremacism, slavery, etc., that doesn’t mean a single thing as far as law is concerned.