Modularity, A distinguishing property of life

We understand that you believe science should define a hard line between living and non-living matter, but reality is rarely black and white. When does dusk become evening? When do foothills become mountains? When does harbor become sea?The transition between all these distinctly different states is slow and gradual, and science believes that the change from non-life to life was also slow and gradual, not due to some sudden event.What does this have to do with the thread's topic, Modularity, A distinguishing property of life, and couldn't you find a reference more recent than the 1902 Encyclopaedia Britannica?--Percy

Huxley's article is an excellent example of Victorian science writing, but his definition of life is more than a century old. As others have mentioned, we have learned much since the 1880's when Huxley likely wrote that article (for example, about the existence of viruses and prions). Any modern definition of life will be more circumspect and nuanced, as well as much more informed. Let's follow your reasoning and see where it leads. So the development of the first life was slow and gradual, but you believe it led up to an "event" which was the beginning of the first life. But unless you believe that unlike the rest of the process that the "event" was something large and sudden, this "event" was just one tiny element amidst all the rest of the tiny elements of the slow and gradual process. How are you going to identify that "event"?The obvious answer is that you cannot. No definition of life could ever cut so fine as to distinguish between two complex chemical systems differing by perhaps only a single molecule, and no consensus of scientific opinion would ever develop around any definition so incredibly detailed, not to mention that our knowledge of the details of life's origin is so sparse that we could not even attempt so detailed a definition anyway.One can see scientific arenas in which the definition of life might be important. For example, NASA needs to be able to report whether it has discovered life on Mars (more for public relations than for scientific reasons), and so it needs a very specific definition. But the origin of life needs no such precise definition. Origins of life researchers are for the most part not very interested in finding where to draw the line between non-life and life. What they're seeking is a realistic natural process by which life might have gradually developed. At what specific point during the process non-life became life is a side issue of not much significance. I don't know which RAZD thread you mean, but there must be at least a hundred threads where this discussion would be more on-topic than it is here. If you decide to switch to a more pertinent thread just post a note here letting us know which one. You're off by 3 and 2 decades respectively.--PercyEdited by Percy, : Spelling.

No one is failing to distinguish between life and non-life. You've offered a couple definitions of life, and we could quibble about the details, but clearly we all accept that life possesses certain qualities that distinguish it from non-life.So no one is suggesting that it isn't possible to distinguish life from non-life. Clear?What we're explaining to you is that in a gradual process of change in minute steps along the path from non-life to life, that the precise dividing line cannot be identified.Here's an example of the ambiguity. Let's say that we agree that living matter is composed of cells that are delineated by cell membranes. We follow the development across time of a protocell that has no cell membrane. At a particular point of development we find that it has acquired a flimsy film around it that is fairly porous to material entering and leaving. After much reflection we decide that this is insufficient to be considered a cell membrane, and that therefore this proto-cell is not living.At a later point in development we find that 10% of the film around the protocell has become an actual cell membrane. Is that sufficient for the protocell to be considered living? We decide not.Later we find that 20% of the film is actual cell membrane, but we again decide that the protocell isn't living yet.Later we find it has grown to 50% genuine cell membrane, and now 20% of scientists think it is living.Later it grows to 75% genuine cell membrane, and 50% of scientists agree it is living.And so on.So at what point is the protocell considered alive?You can't answer that question. And this is just one simple made-up scenario. The realities are far more complex with far more variables and huge numbers of permutations of ways for scientists to disagree.This is why debating about the precise point where non-life became life is a pointless exercise. Origins of life researchers are far more interested in identifying possible pathways.--Percy

You've encountered neither of these caricatures in this thread. Have you considered the irony of asking this question after rejecting expressions of the ambiguity surrounding the dividing line between life and non-life?Tentativity is a central concept in science, so when you complain, "But you haven't proved it," we can only agree with you, but not because theory is wrong, but because nothing in science is ever proved.All that can be done is to offer evidence in support of tentative hypothesis and theory, but no amount of evidence will ever constitute proof. What you really mean to say is, "But you have insufficient evidence for your conclusions," and then we can get into a discussion of the evidence.I'm getting the sense that your real issue is with methodological naturalism, which makes this thread even more off-topic for you.--Percy

You already have that concession, I'll make it again: abiogenesis has not been proven. Everyone here agrees that abiogenesis has not been proven. All the evidence certainly points to abiogenesis, but it definitely has not been proven and never will, just like all else in science.Science seeks only natural explanations. Anything perceptible by our senses, including by means of specialized instrumentation, is deemed to be part of the natural world. This means that phenomena for which we have no means of perception are not part of the natural world, and so are not amenable to scientific examination.We have overwhelming evidence that everything that has ever happened in the universe has been due to natural causes. That this is an accurate observation explains why science's search for natural causes for everything has been so incredibly rewarding. And it's why when science seeks the explanation for anything it seeks only natural explanations. This is not something that is true only for the origin of life - it is true for all scientific investigation. If you object to seeking only natural causes for the origin of life, then you must object on the same grounds to seeking only natural causes for anything in science, whether its electricity, the structure of the atom, or the origin of stars. Any advocacy for unnatural causes lies outside the realm of science. You put your own love affair with hubris on public display first with all your wrongheaded statements made with utter confidence. You were as wrong about the nature of science as you were about subduction.I'm concerned that you might be left thinking that things I don't comment upon were okay, so let let me comment on a few other things. The key issue isn't the speed of the process but that it's made up of extremely tiny steps, nearly a continuum. If it's amenable to scientific study then it happened naturally. You can entertain other possibilities if you like, but you can't call them scientific. I haven't noticed anyone proposing explanations that "have already been proven false via empirical testing." Empirical testing is a means of applying scientific criteria to the study of phenomena, and one wonders how you plan to employ empirical testing of your "other possibilities" that exist outside nature.--Percy

Nothing in science in known with certainty, not even direct observations. All we can do is use the scientific method to increase our confidence in what we know, and that confidence can never reach 100%. You can use the word fact if you like, but then to be consistent with the tentativity principle of science you have to qualify it a la Gould and say "In science 'fact' can only mean 'confirmed to such a degree that it would be perverse to withhold provisional assent.'"Which leaves you saying the same thing everyone else is saying, except that in the meantime you've provided Hyroglyphx yet another thing to be confused about.--Percy

I don't think our views on the nature of science are much at odds, but about this: Hyroglyphx's complaint is about expressions of, in your words, "complete certainty," and even after this short exchange of messages between us I think it very likely that he'll interpret use of the word "fact" as an expression of the "complete certainty" he objects to as inappropriate to science.Abiogenesis is an extremely obvious inference in the context of methodological naturalism where characterization as a fact would not be misinterpreted, but in the broader context of discussions like this that includes supernaturalism and even the Christian God then simple claims of "It's a fact" are bound to be misconstrued.--Percy

I agree with Mr Jack, too. I objected not because I disagree with him, but because Hyroglyphx will inevitably misunderstand. We're already having a great deal of difficulty helping him to understand what we're trying to say, and asking him to grasp yet another subtle distinction is unlikely to help things.Spelling things out more, not less, is the direction we should be going. Once we've gotten to the point where we're confident that Hyroglyphx won't respond to declarations like "Abiogenesis is a fact!" with "What gets under my skin is the surety with which some speak about things that have not been concluded," and "All I ever asked for was concession that abiogenesis still hasn't been proven," and so forth, then maybe we can start using more abbreviated forms of expression.--Percy

And to DevilsAdvocate, too... Isn't biological decay the clear context? And if DevilsAdvocate wasn't thinking along the same lines as you, then I have no idea what he's thinking of when he says rocks decay. That they weather, maybe? That's not biological, either.Hyroglyphx doesn't have a valid point, but claiming that rocks decay in the same way as life doesn't seem like a valid rebuttal, either.--Percy

I've tracked this down, and the "Rocks (inorganic) don't decay" claim comes from Message 130, where Hyroglyphx was agreeing with RAZD, and he clearly identified the context as being biological. DevilsAdvocate was taking the issue in a completely different direction.It's interesting to learn that there are microbes that eat rocks, I'll bet many of us (including me) didn't know this, but I don't think this has anything to do with Hyroglyphx's line of argument in Message 130.--Percy

Yes, I know, I already said that I'd figured out that it was DevilsAdvocate who initiated the digression. I'm just trying to minimize the digressions because of the ease with which Hyroglyphx is distracted from his main point about how confident we are that abiogenesis happened. I guess it makes sense that we'd have trouble maintaining a topic that's off-topic. --Percy

I agree with you completely, and I'd love to see Hyroglyphx pressed on this exact point. The digression had to do with whether rocks "decay".--Percy

Missed this reply earlier. Maybe I'm wrong about the decay of rocks being a good argument, but I didn't get it at first, and someone else thought you meant radioactive decay, plus you're not actually drawing equivalence but only an analogy between chemical decay and biological decay. Hyroglyphx was speaking in a biological context. I suppose you could argue that there's a sense in which the term "decay" can be applied to rocks, but it still isn't biological decay.I don't know if anyone has said this already, but one argument I expected to see is that animals don't begin to decay until they no longer possess the quality of life, or something along those lines. It is formerly living organic matter that is now dead that is most subject to decay, not life.But here's the problem. Hyroglyphx is one of those guys who is simultaneously wrong about so many things that it is very difficult staying on topic. But the point he keeps coming back to is how we know that abiogenesis happened, and I was hoping to maintain focus on that. But I'm not moderating in this thread, just suggesting, and we're already way, way off topic, so if you feel like you're right about rocks don't let me stop you.--Percy

Hi Hyroglyphx,Sorry you didn't like the editorial comment, but let's examine it. Here's what I said: Here's one of the things you said in your reply: This was the beginning of your paragraph summarizing what you feel are our ridiculous claims, so let's examine its accuracy. Has anyone here suggested that there's no such thing as life? I don't think so.You next say: Only Mr Jack has said this, and I challenged it and put the whole "fact versus tentativity" thing in context.Now of course that entire paragraph was written out of frustration, but other examples of errors from you abound in this thread. In your very first post you said this: Your claim that experimental replication was required taught us that you don't understand the nature of scientific investigation, and your claim that proof was necessary taught us that you don't understand the nature of science. You continued making the "proof" mistake throughout the thread.Later you said: This revealed that you don't understand what Pasteur actually demonstrated with his experiments, and so also not the difference between abiogenesis and spontaneous generation.Here's another: You're a veritable font of misinformation.Beyond your lack of understanding of science was the constant pokes you took at others, like these: You also made unwarranted assumptions about the other people here, as here: While we're all of course different individuals, by and large the science people here are not anti-religious. They simply believe that religions can't make scientific claims and not expect those claims to be subjected to scientific scrutiny. Critiquing ideas like the vapor canopy theory or the accelerated radioactive decay theory is not anti-religious, it is pro-science. Besides, since more scientists than not are a member of some religion, for your claim to have any substance would require that many religious people be anti-religious.Then there's this: And this: And this: So don't give us this holier-than-thou crap about how you've been unfairly picked on. You've been dishing out false criticism and sarcasm all through this thread. Develop a backbone and get back in here and start actually discussing things.--PercyEdited by Percy, : Typo.

Whether you continue or not must be your own choice. I've been involved in the creation/evolution debate for over 25 years, and what keeps me going most is concern over the threat to science education. Along the way I have learned a great deal, and the opportunity to learn also plays a role. You flatter yourself. And denigrate others with criticism that applies as easily to yourself as anyone else. And cast yourself as the judge of what is reasonable.My advice is to skip all the editorializing and personal commentary and just focus on the topic. If your arguments are sound then the outcome will take care of itself.--Percy