Science Corner: Viral Frenemies

virus photo

The invisible nature of viruses only makes it easier to fear them. (Photo by AJC )

It’s hard not to think of viruses as our enemies in some fashion. Whether it’s fictional pathogens like the one in Contagion or real ones like ebola, most of us only encounter or think about viruses when they are making us sick. And viruses do make lots of people sick, sometimes fatally, so that impression is not entirely unjustified. As a result, a finding like this one about a virus making a constructive contribution to human embryonic development may be difficult to accept. Admittedly, the “puppet master” language in the news item doesn’t help matters either.

I’ve previously discussed on Facebook (and here) the microbiome, the bacteria of assorted species that call each and every one of us home, and the possible ways it influences us. Having personally come to terms with a role for bacteria in my life, making room for a virus isn’t much of an additional leap. But I can imagine that not everyone would find it so easy to embrace their inner virus. So I’m curious how everyone else reacts to news like this.

How comfortable are you with viruses, ancient ones that infected your ancestors many generations ago, forming a crucial, active part of your genome? What about the suggestion that some of these viruses may play a role in distinguishing us from chimpanzees and other apes, a distinction often associated with concepts of the imago dei?

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Andy Walsh

Andy has worn many hats in his life. He knows this is a dreadfully clichéd notion, but since it is also literally true he uses it anyway. Among his current metaphorical hats: husband of one wife, father of two elementary school students, reader of science fiction and science fact, enthusiast of contemporary symphonic music, and chief science officer. Previous metaphorical hats include: comp bio postdoc, molecular biology grad student, InterVarsity chapter president (that one came with a literal hat), music store clerk, house painter, and mosquito trapper. Among his more unique literal hats: British bobby, captain's hats (of varying levels of authenticity) of several specific vessels, a deerstalker from 221B Baker St, and a railroad engineer's cap. His monthly Science in Review is drawn from his weekly Science Corner posts -- Wednesdays, 8am (Eastern) on the Emerging Scholars Network Blog. His book Faith across the Multiverse is available from Hendrickson.

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    Kenneth Litwak commented on June 17, 2015 Reply


    If human existence is the result of an infection, then any notion that the biblical God had anything to do with human existence is extinguished for me. It’s hard enough to consider reading the biblical text regarding God’s involvement in human existence, e.g., Genesis1-2, Psalm 139, Romans 1, etc. could be read metaphorically enough to allow for evolution, but if humans are essentially an infection–as some environmentalists claim–then any claim for human existence in the Bible as “good” or any talk of the dignity of humans seems to me absolutely indefensible. Of course personally, I see no way to explain human consciousness as merely the result of random mutations, and perhaps that puts me outside the scientific boundaries completely, but that would be part of the point. If everything about humans is explicable as a genetic mutation, then there is really no reason to believe in anything non-material, is there? In such a case, I think that it is intellectual suicide to continue to hold Christian beliefs. I’m dead set against trying to have one’s epistemological mutation-only cake and eat it too.

    Ken Litwak

      Andy Walsh commented on July 9, 2015 Reply

      Well, even if these particular results are correct, I wouldn’t go so far as to say that human existence is the result of an infection. At least not in the sense you seem to be suggesting, that the only reason human beings exist is because some kind of critter happened to get sick with a virus in the past. That’s a bit like saying that the only reason I’m writing this comment is because the Germans used very sophisticated cryptography in WW2. Yes, breaking those codes was part of the sequence of events that also includes the invention of computers and the manufacturing of this laptop, but there are plenty of other ways computers could have been invented.

      One could also say that that particular infection event was redeemed by the resulting genetic material ultimately being repurposed for a role in the development of human embryos!

      I also wouldn’t say that one has to read the Bible passages you cite “metaphorically enough” to allow for evolution. For one, I’m not sure language fits so neatly into a single linear spectrum from completely literal to completely metaphorical, nor that completely literal is always best. More to the point, I don’t think it’s so much a matter of degree of metaphoricalness as level of description. A classic example is boiling water on a stove. It is perfectly accurate to describe the process in terms of the physics of molecular motion, or the chemistry of combustion and heat transfer, or the mechanics of knobs and igniters; it is also accurate to talk about a human being wanting a cup of tea. These are parallel descriptions, each complete on its own terms, each accurate, and also complementary to each other. Likewise, I think it is compatible to describe creation in terms of natural mechanisms and also in terms of God’s agency without having to call one description metaphorical.

      Elsewhere, you talk about God not having physical organs in the sense that you or I do. I think the same would hold true for physical hands. Thus the mechanism of God’s creation could conceivably seem hands-off to us, not because God is actually detached or removed from the process or only indirectly involved, but rather because our understanding of how God works is limited by our understanding of how we ourselves accomplish things.

      As for consciousness… that’s a pretty big topic, and a trickier one since many questions remain unanswered. Personally, I think we will find that humans are inextricably embodied beings, meaning that we cannot exist independent of some physical embodiment. I think that is consistent with scripture, which links body and soul and which promises a bodily resurrection. I think that is one distinction between us and God, who as far as I can tell from the Bible can exist independent of embodiment; at the same time, he is also capable of embodiment as demonstrated in the person of Jesus. Within that framework, I think there is still a lot of latitude and a lot of potential to learn more via scientific inquiry.

        Ken Litwak commented on August 11, 2015 Reply


        Sorry to be slow to reply. Let me return to the language issue with you. Aware that if I were a scientist I might nuance this some, but I have a hard time with saying humans are the result in part from a viral agent (if you don’t like the word “infection,” though I’m not sure why), and have junk DNA in our cells, and have various organs and other physical properties that scientists would explain as the result of random genetic mutations, and at the same time affirm, “Let us make humanity in our image, according to our likeness” (Gen 1:26a). That stretches the idea of “make” rather far, doesn’t it? Wouldn’t that be sort of like Henry Ford taking credit for an F-15 because it was produced on an assembly line and has engines that burn petroleum products?

        Paul seems to rely upon Genesis 1-2 when he tells Christians in Rome that God’s power and divine nature are evident to all in what has been made to the point that any humans who do not recognized this are held accountable for it. Yet, apparently if I’m to be scientific, I actually have to say that what exists is mostly random–bearing no evidence of design at all.

        I resorted to metaphor because I cannot see any way in which either Gen 1:26 or Rom 1:20 could be seen as “true” in taking the language in any “normal” way, in Hebrew, Greek, or English. That is my stumbling block. That is why I cannot accept macro-biological evolution. None of the skills I’ve learned for doing exegesis help at all in understanding these biblical texts if I read them as I imagine the original audiences did. They would surely have understood these to mean that there is a Creator who is responsible for what exists as the agent in creation. It might be just me, but I cannot see any way to make “make” (Hebrew ‘asah’) mean God is directly the agent in a process that scientists claim needs no external agent. Whatever Genesis and Romans are saying, and however they are saiyng it, must have been, I would argue, intelligible to the original audiences, just as John Walton would agree tah these texts were written to ancient audiences, and not to us. (I disagree with his reading of Genesis 1, but that’s another story.) Can you help me out with a bridge from the biblical text to the microbiology lab?


          Andy Walsh commented on August 16, 2015 Reply


          So, what does it mean to make something? That’s an important question, and at the core of creation. Of course, the most immediate image that comes to mind is the artisan fashioning a table, a dress, a ring, a violin, what have you. And indeed, the same word that appears in Genesis 1:26 for making appears later in the Old Testament when various craftsmen make the physical objects for the tabernacle. Making is something we do with our hands; what could be simpler?

          Well, as soon as we starting talking about God making it gets complicated. Outside of the incarnation of Jesus, it’s not clear that God has hands; in fact, as I understand it, orthodox Christianity would assert that God does not have physical form at all. So when God makes something physical, what does that actually look like?

          Further, do we wish to say that God only made things for which we can demonstrate no natural process? Doesn’t Psalm 139 say that God made David? Science has told us all sorts of things about where babies come from; a metaphysical naturalist would say that no divine agent is necessary to explain the birth of each human. For me, I wouldn’t say that what God makes is restricted to the very first instances of anything biological, and all subsequent living things are merely the result of purely materialist processes. I would say instead that God continues to create or make living beings and that we also understand the mechanisms by which that creation comes about in terms of genes and gametes and cells and so forth. (Jim Stump gave a good talk at BioLogos on the language and conceptual issues around a both-and view of how God’s agency and mechanistic descriptions relate: .)

          Of course, things are always a little more complicated when we talk about God’s nature, so maybe we should stick with human activity. When an artisan makes a table, does it matter that she has to start with wood that someone else cut down, and yet another someone processed into lumber, or that she used tools made by yet more parties? Who actually made that table? And isn’t it really just a bunch of molecules bumping into each other, following well-known rules of physics?

          We also say moms make babies, but again we also know about cell division. And what about less tangible creations? When a composer writes a symphony, has he made music? No sound waves were produced, except maybe pencil scratching on paper or keys clicking on a keyboard. It is the orchestra that produces the sounds we hear; did they make the symphony?

          What about ant colonies? Clearly the ants make those, and yet no single ant conceived of or designed the entire structure, indeed it’s not even clear any single ant is aware of the entire structure once its complete. So who made it?

          We might appeal to the Hebrew word, but from I can tell there’s not much help to be found there. It seems to mean a variety of things, including the fairly generic “to do”. In light of all these thoughts about making, I see no conflict with the text of Genesis 1:26 to say that God made man in his image, God made David, God continues to make, and God has made and continues to make in ways that can be apprehended via scientific inquiry. To me, such a God is substantially more knowable than a God who did all of his creating in the distant past via inscrutable processes. And passages like John 1:18 suggest to me that God is knowable and wishes to be known. And it is precisely because God is knowable via scientific inquiry that I think Romans 1:20 still remains true via a normal reading of the language.

          As for the other bits of language: I was reluctant to use ‘infection’ simply because I think that implies for most people some kind of illness. Not all viruses cause illness, and it is certainly possible that those retrovirus genes were acquired without any of our ancestors becoming ill. ‘Junk DNA’ is one of those unfortunate misnomers that routinely happen in science because we have to name things before we really understand them. It was dubbed ‘junk’ because it doesn’t make proteins, but we have since learned DNA does lots of other important things besides code for proteins, and thus is anything but junk. As far as I know, biologists from the whole range of world views now regret the name ‘junk DNA’ and agree it isn’t actually junk.

          The word ‘random’ is admittedly tricky; it is used widely to mean a variety of things. Mutations are definitely random in the sense that we humans cannot fully predict them individually. Other senses are more difficult to assess on a purely empirical basis. Having already affirmed that God is creating through mutation, would I say mutations are completely without purpose? No, I don’t think I would go that far; to know that for certain would require a statement of (non)intent from God. When a scientist asserts that mutations are purposeless, that scientist is really just saying she doesn’t know of any purpose, which is a more limited statement than being able to rule out purpose absolutely.

          Here’s how I think about mutation. Mutations are a means of exploring the abstract space of life — the space of possible ways to arrange chemicals and make something living. That space was created by God; it is encoded in chemistry, in physics, in the way the universe works. (This talk by Ben McFarland expands on this topic: One cannot get away from God and God’s creation by moving around in that space, since God created it.

          But all that abstraction is hard to imagine. So instead, imagine Adam & Eve strolling through the Garden of Eden. They have no destination in mind, they are exploring. They spy some beautiful flowers in bloom and walk over to get a closer look, to breath in their perfume. Then they hear a brook and wander off to find the source and enjoy a cold, refreshing drink. From there they follow some deer until they get hungry, so they make their way to a fig tree for a snack.

          From a bird’s eye view, their path probably looks random. Adam & Eve themselves couldn’t have predicted the path they would take. And yet they are exploring a place that God made — God made the flowers, the brook, the deer, the fig tree and the figs. Could we say that their path was made by God?

    Ken Litwak commented on September 7, 2015 Reply


    Thanks for your response. Sorry to be slow to respond. I’ve recently started a new position as a librarian at a seminary, and there are some complexities to moving.

    Let me take only one aspect of what you have written: Psalm 139 and mutations. I have actually thought about this specific thing quite a bit. Let me start with the psalm. David wrote that God originated him and wove him in his mother’s womb. I think that a few things need to be said here. First, I doubt, though I of course could be wrong, that God revealed to David the precise nature of how humans go from a fertilized egg into a full-tem baby. Therefore, David is being poetic in his assertion that God made him. Second, I think we need to approach this statement carefully. If we take it, with the scientific knowledge that we have today about reproduction, we would be justified in seeing this as implying at least that God chose our genetic code and caused us to come into existence.

    Can that really be so? Does that mean that God deliberately chooses for rape and incest victims to conceive babies? I have difficulty with such a view. It does not sound like the act of a Good God. It might also mean that we need to see all mutations as being engineered by God, but that runs into the same theological difficulty. That makes God responsible for babies born without limbs (which I gather, though I have not researched it, seems tied to pregnant women being given Thalidomide). It makes God responsible for babies born with no brain, with their external organs on the outside of their body, and a host of other maladies, some life-threatening, others reducing the quality of life. I have had the opportunity to live with a significant mutation myself. I was born with a complex of rod-cone dystrophy, Nystagmus, and eye lids that do not on their own open very far, so that making good eye contact is next to impossible, and can give the impression that I’m half-asleep—even on the rare occasions that I ride on big roller coasters. My wife and I once took our son, who unfortunately inherited my mutant, defective eye genes, to a pediatric ophthamological geneticist at Stanford (now there’s a specialization!). She looked at his eyes and then my eyes, and then his, then mine, and told me that she was aware of fifty kinds of rod-cone dystrophy, and mine isn’t like any of them. Isn’t hat special! This has been a cause of difficulty my whole life. When I was in high school, no one had any concept of making accommodations for disabilities. It is hard to follow math being worked on the board, when you cannot see the numbers. I’ve done some fairly complex computer programming, but never taken calculus because learning math is so hard because of this condition. Am I to acknowledge God as the direct Cause of this, um, opportunity??? I suppose an ardent Calvinist might assert that all these mutations are foreordained, but I think most Christians would view them more as the result of the Fall. If God did foreordain my mutation, then He is directly responsible for me failing the one on-campus teaching position interview I had. (The search committee chair told me the faculty was concerned about my eye sight.) So I am not sure how far to press the language of Psalm 139.
    The mutations caused by all the rogue, parasitic DNA that enters our cells and can never be gotten rid of does not sound like something a Good God would design either. Are all these bad mutations part of being made in God’s image? I hope not. However, it would make the question of theodicy much easier to address if God were directly responsible, as David’s words could be taken, for all the harmful mutations humans have. Then He truly would be the Author of Evil, and there would be nothing more to say as I consider the massive pain and suffering, to say nothing of extinction, required by billions of years of evolution, to so many animals, not to mention humans or their predecessors.

    As a related issue, I have said this before, but I am not aware of any human who has experienced a positive mutation that happens on the same big scale as the sorts of things mentioned above. Someone might be born with a natural immunity to some disease, but that is hardly on the same level as being born with Down’s Syndrome, or with severe eye problems. (If I had known that my eye issues were genetic I would have avoided marriage in order to avoid cursing my son with this huge burden—hardly something I would want to credit God with.) So are we fearfully and wonderfully made, or the result, as your viral example suggests to me, random, unfortunate mutations among living creatures? How are the many people with decidedly negative mutations evidence in nature of God at work? What do they show about God’s divinity or power? I have no answer, and this is one of the problems I have with evolution. It is not that the theory disproves there’s a god. It’s that bad genetic mutations, parasitic DNA, etc., do not require a god to explain it. Rather, it seems to me, these remove any reason to invoke a god at all, let alone the Good God of Scripture. That is why the whole evolutionary issue is so troubling to me. If we don’t want to have a God of the Gaps, and we do not want to credit the God of Scripture, in whom we believe, with deliberately cursing humans with most mutations, then it does not appear to me that there is any need for God at all, except for creating life in the first place. That has created for me a theological crisis, and I can well understand why people who start of college as Christians, study biology and then reject the Christian faith.

      Andy Walsh commented on September 12, 2015 Reply


      No worries about the timing; we all have lives outside this blog. I hope that the new position you mentioned is starting well, and that this employment opportunity will be a blessing to you and your family.

      Thank you for being so candid and vulnerable in what you shared. It makes perfect sense that living with those particular conditions would have a strong influence on how you view mutations. And obviously nothing that I say is going to change the reality of your experience for you, or the reality of your son’s experience. So I hope that nothing that I say (or have said) gives the impression that’s what I’m trying to do.

      I agree that interpreting the Psalms is challenging given their poetic nature. I want to affirm with David that God authors individual human beings. I personally don’t think that means we need to interpret Psalm 139 as meaning that God chooses each individual base in each individual genome. For one, as you note, it seems very unlikely that God revealed those kinds of details to David, so it’s unlikely that was the message David intended to convey. Second, I don’t believe that’s how God interacts with his creation. I would say that God collaborates with creation in authoring human beings, such that creation has some freedom of choice in the process. These choices can include, but may not be limited to, individual mutations.

      Now, that may seem like I’m trying to eat my cake and have it too, to say that God has a role in the development of each person but that he is not deliberately choosing each individual mutation. I’ve discussed previously on the blog how I think the mathematics of chaos theory make it plausible to hold to both of these ideas simultaneously. That post doesn’t discuss mutations in particular, but the fact that so many different genome variations result in viable humans is an indication to me that something resembling the robustness and grace of chaos math is involved in human development.

      You asked about positive mutations that balance out, at least on the population level, the various negative mutations you discussed. I think this is a challenging question to answer because we tend to notice and study the ones that have negative consequences because we want to find some way to treat or prevent them for medical purposes. Are there particular mutations that make it possible for exceptional athletes to be exceptional, or that allow some folks to excel at art, music, or science? There’s some research on those topics, but my sense (which could be biased or wrong) is that we don’t study those kinds of things as extensively. Still, I’m not sure how we would decide which ones were positive enough to balance out the negatives. Is there any amount of benefit someone else could have that would make you feel as if your own experience was adequately balanced?

      Instead of focusing on specific mutations, let’s try a different tact. From the perspective of evolutionary biology, everything is a mutation. There isn’t some Platonic ideal human genome such that only the bits of our genomes that deviate from it are mutations. And if there were such a thing, wouldn’t that imply that all mutations were negative since they deviate from the ideal? But like I said, from an evolutionary perspective, there is no such thing. So another way to answer the question of whether there are any positive mutations is to say that anything good that comes from our genetics — our ability to walk outside and feel the sunshine on our skin, to hear a sublime symphony, to taste an especially delicious slice of pizza, to talk with our fellow humans — these are all the product of mutation.

      Another thing that comes from an evolutionary perspective is the realization that we are all transitional forms. Evolution hasn’t stopped; it’s always happening. Where it’s going is hard to say, but we are all part of the transition from where life has been to where life will be. And the tricky part of being a transitional form is that it can be awkward, uncomfortable, or difficult. You have differences that set you apart from everyone else; you may not be a perfect fit to the world around you. When I think about this part, I think about my son. He has an autism spectrum diagnosis. One way that manifests is challenges with communication; nonverbal cues are harder for him to pick up on and eye contact is uncomfortable. Face-to-face chats are tough, but in some ways text communication (like e-mail or blog comments) are a better fit for him. Will he be better prepared for a future with more electronic communication? Maybe; I don’t know for sure and not everything about the autism spectrum suggests it is an adaptation to the Internet. But I think it does hint at how some of our challenges from being transitional forms are the result of living in a world that isn’t quite the right fit. And isn’t that one part of the Gospel? That we will find this world somewhat awkward and uncomfortable because we are meant to live in the new creation? And indeed, the more we transition via sanctification, the more acutely we will experience that mismatch.

        Andy Walsh commented on September 14, 2015 Reply

        One more point of clarification that occurred to me — when I talked about being in transition, I didn’t mean to suggest that any and all mutations are preparation for whatever is coming in the future. I simply meant to emphasize that the adaptiveness of any given mutation is contextual. There may be some mutations that aren’t a good fit for any conceivable context. But all mutations have some context where they aren’t a good fit. Which means we are all likely to find ourselves in a situation at some point to which we aren’t perfectly biologically adapted.
        And I think that speaks to why God would even bother with mutations in the first place. After all, we might ask why he doesn’t instead make everyone perfectly biologically adapted to their situation? I think the answer is because such a state could only ever be transient; the first change in external conditions could render that perfect fit suboptimal. Thus there is a need to have some flexibility and diversity for different conditions. And since individuals can’t change their personal genome on the fly, that means we need a diversity of individuals at any given time to help smooth out the suboptimal fits. I think that’s one reason why the Bible places so much emphasis on community and the body that is the church, so that those who are better adapted to any given situation can help out those who aren’t. And thus I think the fullest expression of humanity is not some singular idealized human genome (because, again, ideal in what context?) but rather the full range of human genomes.

          Ken Litwak commented on October 8, 2015 Reply


          Thanks for your reply and this addendum to it. You have offered some interesting points.There are some questions I would ask.
          1. The way that you described humans as a transitional form led me to wonder about two things. First I wondered what we might transition to, smart as the Asgaard? Second, and more seriously, that would suggest that the author of Genesis is wrong. Humans are not a distinct creation of God. We are just whatever random thing came along after whatever came before.I’m particularly struck by the homo sapien mutation being in part the result of random,rogue (virulent) DNA in our cells. Somehow, that does not seem like humans are what they are because God designed them in any way.

          2. I understand your point about adaptation–mutation–being necessary to survive in a given context. What I gather from what you have said about viruses and what I’ve read elsewhere on this point (such as Rick Collings, author of Random Designer), would be something like, “mutation happens,” and that is the way things work. That is how all living things have come into existence (except of course for the first life form, which many scientists insist is likewise a random accident–do I need to accept that scientific assertion to?). I can;’t help wondering why God would such an obviously flawed approach. No irrelevance is meant here, as any Being smart enough to design DNA would surely be capable of dong better than evolution does. What do you think?.

          I am a firm believer in the idea that ideas need to be pushed to their logical conclusions. When I do that in this case, it looks to me like humans are no more or less designed or intended than clams, crayfish, crows, or chameleons. That does not seem to leave space for being made in God’s image, since we have the same basic origin as all other creatures. Furthermore, if we are a transitional form, will all future mutations from homo sapiens also be automatically in God’s image, whatever that means?

          3. I find interesting your statement that God is always at work creating. I am wondering why you think that? Looking at all the “bad” mutations that make survival harder if not impossible, and all the violence that occurs through predation because the evolutionary process led to predators that kill in very violent ways. it is hard to see the hand of the God of Scripture present and creatively at work there.

          4. A common issue for Christians, and raised by those who reject the Christian faith is theodicy-, the problem of evil. It is fairly common to read or hear people explaining some of the evil in the world, such as bad mutations, as the result of the Fall. However, so far as I can tell, an evolutionary understanding of the origins of all life on earth has no place for a Fall. There was never a “very good” state to fall from. The only difference between us and what are often suggested as human predecessors is that we have more sophisticated ways to kill humans and other species, but there is not any reason to think that there was ever a time when our species was not as violent and oriented toward evil as we are now. Humans could not have committed the first sin because we were never sinless. How would you understand the Fall?

          Indeed, the story of the Fall is made even more implausible by scientific claims that the first human male and the first human female arose separately from large populations. I’ve never quite understood the claim that we should not conceive of a fist male or female hum an because they arose in a large population. The odds of several female somethings giving birth to homo sapiens essentially simultaneously seems rather unlike IMHO. There had to be a first human male and a first human female, regardless of how many creatures were present when that took place. Sorry for the digression.

          My point is that there isn’t any reason to think that the population from which humans arose was not violent as well. Indeed, there are violent species through all the phyla I know of, depending upon how one defines violence, so which one committed the first act of violence that could be called “sin”?

          This does not mean that I am trying to read Genesis as a scientific account. I am reading Genesis to say that God is the author of all things, that creation is good, and that human creation is very good, but that at some point, the first humans turned from their creator, and that has had a major effect on all of creation (see Rom 8:19-29 for the effect of sin on all of creation). In an evolutionary model, however, I just don’t see how there could have ever been a “good,” let alone a “very good,” that humans somehow spoiled.

          I mentioned theodicy above. If all living things are the product of evolution, and God is always at work “creating,” i.e., influencing evolution somehow, then is God not responsible for all the bad things that come through mutation? If God designed the evolutionary process, it does not seem appropriate to say, “well, he made that genome, but not this one over here.” If God is not always at work influencing the evolutionary process, then why think that he is involved in it at all? For the author of Genesis, who wold have had no idea about DNA, let alone evolution, evil is a perversion by humans of the good that God made. In an evolutionary model, whatever happens just happens, I don’t see a way to avoid having your cake and eating it too, unless we completely remove God from the evolutionary process. Then whatever happens just happens. I would sincerely like to know how you see this instead of how I see it. Thanks for the ongoing dialogue.


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