The Transporter Test & The Copy Problem: The Three Camps of Brain Preservation

Would you like to live again after death? If so, are you a Reanimator, an Uploader, or an Uncertain? Take the test & see.

The first in a series on brain preservation technologies, options, and policy.

John M. Smart, Michael Cerullo, M.D., and Keith Wiley, Ph.D.

Robonaut vs Astronaut (NASA 2015)
  • Would you believe me if I told you that within fifty years, the vast majority of us will live in societies where death is no longer the end of our individual lives, if we don’t want it to be?
  • Would you believe that within the next two generations, if we continue to work hard on the right problems, anyone who wants to, almost everywhere in the world, should be able to ask their health care workers to carefully preserve their biological brain after they die, so that they and their friends and loved ones can come back together to later life?
  • Would you believe that option will eventually be covered by public health care in most societies, making it free to anyone who might want it?

You probably wouldn’t believe any of these claims today, unless you’ve been exposed to the rapidly advancing sciences, technologies, laws, and philosophies of identity that argue brain preservation may soon be an inexpensive and validated option for living on, and returning to life, along with ones friends and family, in a more technologically advanced world.

Death is a deeply personal loss, and we all face it as best we can. Choosing brain preservation at the end of life will never be for everyone. But we believe people deserve to have as many good options for facing death as our current science and society can offer.

Brain preservation is one such option, one that offers a realistic possibility of living again in an advanced future world, along with loved ones and friends. Our nonprofit, the Brain Preservation Foundation (BPF), is working to make this option as validated, affordable, and accessible as we can.

People who are presently at least a little bit intellectually curious about making the brain preservation choice at the end of their lives are a small but growing demographic. In his 2012 ebook, David Ewing Duncan estimated them at 1% of the population of most developed-world societies, and a likely smaller fraction in traditional societies. That’s a small percentage today, but it is already a large number of people who deserve representation.

We believe this group will grow as the cost and accessibility of brain preservation drop with technologies now in the lab, and as neuroscience provides validation that brain preservation preserves retrievable memories in animal models. Such validation will happen by cracking the neural code (learning how memories are stored in neural ensembles), which may happen surprisingly soon, as neuroscientists can now manipulate ensembles optogenetically in animals. Another kind of validation will occur when neuroscience can read a memory from a well-studied neural circuit (ensemble system) in an animal model, after that portion of the animal’s brain has been preserved, scanned and “uploaded” as a computer emulation. Many neuroscience labs are working on both of these problems today.

Validation that our consciousness might return in a future emulation may also begin to come in the next few decades, as we finally discover and define the physical basis of consciousness. Perhaps our best model for consciousness today is that it emerges via a special process of neural synchrony in a highly globally connected brain structure, the claustrum. See the claustrum’s Wikipedia page for exciting recent evidence for this model. Once we understand consciousness mechanistically, some computer scientists may put rudimentary forms of consciousness into our deep learning computers. Those deep learners may well work better as a result. Let us hope ethicists and society regulate that work, as we’re all truly entering a Brave New World.

In the foreseeable future, some of the preservation technologies we study at the BPF may allow the costs of the most affordable brain preservation services to drop so low, perhaps as low as $5,000 instead of the current $80,000, that an increasing number of people will make the preservation choice at the end of their lives, rather than paying for it up front with life insurance as is usually done today. As the number of people who have made the brain preservation choice grows, and everyone knows someone who has done or considered doing it, we can also envision a world where these costs are fully covered by health insurance, and the services are available everywhere, to anyone.

The currently preservation-interested demographic can be easily divided into three camps, each with different expectations for the future. The folks in each camp don’t always understand or talk to each other all that well, but they need to learn to get along.

This post will offer you a single-question, which we call the Transporter Test, to reliably sort you into one of the three camps of folks who are at least a bit curious about doing (or have already made plans to do) brain preservation when they die. The test will also help you understand your own current beliefs with respect to an important but mind-bending concept in personal identity, a concept that philosophers call the “copy problem.”

Who should read this post? For starters, anyone in the reading audience who doesn’t expect to see biological aging cured in their lifetime. Today, all mature, undividing cells in all living organisms accumulate errors and trash, and all our dividing cells become increasingly damaged and cancerous. While we can slow these processes down, and we may even mostly arrest cancer, we know of no credible theories or evidence that we can stop the aging process itself at the molecular scale. It’s just far too hard a problem.

Now for the good news: If neuroscience and computer science continue their currently rapid rates of advance, the brain preservation choice, while expensive, of uncertain value, and available in only a few places in the world today, is going to get much more affordable, evidence-based, and accessible in coming years. With that in mind, let’s take a tour of the three main ways folks tend to think about this major life choice today.

Here are the three camps:

Camp 1 — Reanimators

Cryosleep (suspended animation), (Avatar, 2009)

Reanimators either desire, or expect it will be necessary, to repair and reanimate (bring back to life) themselves in the form of biological bodies, in order to live again. They believe or expect, with a greater than 50% probability (and for some, essentially 100% probability), that their personal identity (personality and self-awareness) arises out of the unique physical and informational features of biology. Thus they think human minds need to be biological in order to exist.

In philosophy of identity, they favor what is called the “body identity” or “biological identity” theory. Some reanimators also believe or expect, again with greater than 50% probability, that their own personal biological matter (including their brain’s existing molecules at death) will have to be repaired and reanimated in order for them to come back. Philosophers call this the “material identity” theory. Reanimators hope to perfect a technology some call “reversible solid-state suspended animation,” the ability to cryonically preserve and later reanimate human beings and brains. That is an exciting vision, and we can certainly expect some progress on that front. See this great Economist article, Wait not in vain (2016) for examples of the new tissue and organ preservation strategies being tried in labs around the world, with the near-term goal of expanding tissue and organ banking in medicine.

Without the benefit of a formal survey, we think the majority (at least 60%, in a first guess) of people who have presently done cryonics, (low-temperature preservation of their brain or body at death, for the possibility of living on), or who are seriously interested in it, are reanimators. This includes most older cryonicists and most Alcor and Cryonics Institute members. Reanimators identify very strongly with their biological bodies and want to come back in them. Because they love life and have usually lived long biological lives, it’s easy for them to assume that biology is the only way to get back to all the amazing things that life has offered them so far. Are they correct in this assumption? We shall see.

Camp 2 — Uploaders

Uploading (Transcendence, 2014)

Uploaders are patternists,” meaning they believe or expect, with greater than 50% probability (and for some, essentially 100% probability), that the functional abilities (informational and computational patterns) of their biology are their true self, not their biology, which presently carries that pattern, and not their matter either, which changes constantly during their lives. Another way of defining an uploader is that they believe or expect that there is less than 50% probability that repair and reanimation of their biology or their matter will be necessary in order to wake up in the future. They expect instead to be scanned and uploaded, and wake up as a technological mind, inside some kind of technological body, in a future environment.

This brain scanning and uploading technology is already much farther along than most people think. For example, neuroscience labs around the world are already using automated FIBSEM machines (a kind of electron microscopy) to scan and upload into computers detailed connectomes of small animal brains, including flies, zebrafish, and even parts of mouse brains. We don’t yet understand how to read memories from these digital connectomes. But give it a little time. Lots of folks are trying to crack that puzzle right now.

What neuroscientists have recently done is some truly sci-fi feats like removing individual memories and even implanting fake memories into mice by shrinking things called dendritic spines and synapses inside a living mouse’s connectome, using lasers and optogenetics. I’m not kidding. See the TED talk by Steve Ramirez and Xu Liu (2015) below for more.

Steve Ramirez and Xu Liu, A mouse. A laser beam. A manipulated memory. TEDx Boston (2015)

So we’re getting ever closer to understanding the way the brain’s neurons (connectome) physically store individual memories. We know that most of our memories are smeared out across the differently-weighted connections in a large set of neural networks. Storing memories in networks makes them especially useful (simultaneously accessible to many different “mindsets” or perspectives, so we can argue with ourselves), and also particularly resilient, able to re-create themselves, even if any one link is damaged, simply by reactivating the undamaged parts of the network. That “re-creation” of memory is very likely what happens when you finally remember a person’s name by thinking about another aspect of the person that you can easily recall, or remember what you wanted to do by going back to the place where you formed the memory, a few minutes ago.

Neural networks also make us masters at dimensional reduction, which is the constant challenge of taking massively multidimensional sensory input and seeing useful patterns in in it, patterns that are represented in a much smaller number of final dimensions. Dimensional reduction (of masses of training data) is what our deep learning computer hardware and software is learning to do so well today, which is why AI has recently made so much progress. It certainly isn’t all of what a human brain does, but it is a very important part, recently ported from biology into our technology.

Philosophers call this camp the “functionalism” or “psychological identity” theory. Uploaders believe their memories, personality, and consciousness are substrate-independent”, meaning they can be moved into any substrate that has sufficient pattern complexity, whether it is biology or technology. As evidence, they note our recent advances in deep learning , and the growing number of technologies, called neuroprosthetics”, that functionally replicate features of our hearing, vision, and other parts of our biology, and deep learning neural networks that now replicate many features of biological neural networks, including sensory processing and memory. This replication process always starts out crude and imperfect, but it gets better as we learn all the critical patterns in biology that must also exist in the new substrate.

Some uploaders cite the Moravec transfer, from Hans Moravec’s Mind Children (1988), a proposed process of replacing one’s biological neurons, bit by bit, with nanotechnological substitutes, to maintain “continuity of consciousness” during the upload. While this proposal has the benefit of being easy to conceptualize, others have argued continuity of consciousness is an illusion, and it is easy to argue that any such nanotech-dependent procedure will likely arrive later, be less effective, more expensive, and less popular than brain scanning and uploading. In the uploader’s view, if you’re just a pattern, keeping that pattern preserved is all that matters. Not the matter.

Uploaders are often younger cryonicists (teens and 20’s especially), or they have a computer science, neuroscience, or computational neuroscience familiarity or background. Based on conversations within these communities over the years, and in monitoring online conversations about these topics in communities like r/Futurology (now with 6.5M “futurists”), we’d presently estimate (again without benefit of a formal survey) that uploaders are on the order of 10% of those interested in cryonics today, and their percentage, along with the evidence they offer for their position, is presently growing.

Uploaders note that just as deep learning computers are clearly accelerating in their learning abilities versus biological brains, technology offers some major apparent advantages over biology for representing, storing, communicating, and updating our future mental patterns. They note the millionfold improvements in speed, the near-perfect memory fidelity, the unlimited flexibility, and the much faster resource efficiency improvement trends in computers relative to biological brains. Uploaders usually grant that they might come back in biological form, and they generally would like that future option. But many expect they’d rarely, if ever, become fully biological again. If they did, they’d likely do so with only part of their future selves. Most of their future patterns would likely continue to be postbiological, as the capacity for continued personal growth and evolution appear to be so much greater in technology. Are uploaders correct in these assumptions? We shall see.

Camp 3 — Uncertains

“Two roads diverged in a wood, and I took the one less traveled by” (Robert Frost, 1920)

Uncertains as their name implies, don’t yet buy the arguments of either of these two camps, which puts them firmly in a third camp. They usually talk about cryonics and brain preservation as an “experiment” or a “bet” that they’d much rather make, given the alternative experimental groups, that of either certain death or a religious afterlife. If asked, they might put the odds for reanimation being necessary for them to come back at something like 50/50, or simply unknown.

Some uncertains will grant that neuroscience and computer science now argue that human memories are stored in a small set of stable molecular features (most importantly, dendritic spines) in biological neural networks (connectomes), and that if these networks are well-preserved at death, then our life’s memories can very likely be scanned and uploaded to future computers, to share with our loved ones or the world. But they are typically agnostic on the question of whether all the brain’s functions, including emotion, personality, and consciousness, are substrate-independent.

Uncertains point out that quantum states cannot be cloned, according to quantum theory. That means the precise quantum states of your current biological brain would not make it into your upload. But would they be similar? And do quantum states even matter? We don’t yet know. The majority opinion of current neuroscience is that they are irrelevant to our higher features of mind. But we will have to see. If they are, let’s say, 10% relevant, to pick an arbitary number, that might mean only 90% of you would make it into your copy. Reanimation might feel like waking up after, and now having to recover from, a debilitating stroke. But even that might still be acceptable to many of us, when faced with the other options. These are thus very personal choices, based on uncertain science.

Without a formal survey (anyone want to volunteer at BPF to do one?), we’d guess that around 30% (the remainder) of those who have done or are planning to do cryonics, or who have seriously considered brain preservation, are in this camp. Uncertains remind us that definitive answers to many of these questions are still unknown. We still know little about the deepest questions of neuroscience, including consciousness, and the nature and limits of physics and information in both biological and technological systems.

Why aren’t the majority of cryonics members in the uncertain camp today? One reason may be that the current cost of cryonics is so high. At $80,000 for a neuropreservation at Alcor, for example, members tend to have a well-reasoned personal belief that at least one of the first two camps are likely to work. Most folks don’t spend $80,000 on a hunch. Instead, they tend to develop a personal set of future beliefs, and unfortunately, “I’m not sure” isn’t as attractive a belief as it would be if we were all being more scientifically-minded, given the current limits of our knowledge about the consequences of this choice. Another reason is that as materialists, we know our biology is at least one proven material foundation for the making of our minds. So it makes sense that reanimation is the most intellectually attractive camp for those thinking about cryonics, at least at first.

Ready to see which camp you reside in at present? Let’s take a test.

The Transporter Test

Star Trek Transporter (Star Trek: The Next Generation, TV Series 1987–1994)

A good way to find out whether you are presently a reanimator, an uploader, or uncertain, and whether you have an instinctual bias to reanimation, as most folks do when they first engage with these ideas, is to take the Transporter Test, answering a question that will help uncover your assumptions and feelings with respect to the “copy problem.”

The Transporter Test: Would you go through a Star Trek transporter (molecular scanner, disassembler, pattern storer, beamer, and reassembler, using new molecules at the other end) if many others had already done it as a new form of travel, they claimed to be themselves on the other end, and as far as anyone could tell they seemed the same? Or would you not go, unless forced, because you presently believe the process would cause your own death as your brain was being molecularly disassembled, and your new brain and body would only be some kind of copy that falsely “thinks” it is you?

This is actually a deep question, as your answer depends on your view of the nature of personal identity. What’s more, your answer may change over time. This helps us understand why all three camps exist today, and why some folks move between the camps as they learn more about the world. As progress continues in neuroscience and computer science, some folks will change their minds. So as you think about these issues, feel free to move around, hang out for a while in a different camp, and see if that group of people feel more like home.

If you are not willing to go through the transporter today, you’re very likely a reanimator. You think your biological body is your identity, the philosophical distinctions of “original” versus “copy” still matter to you, and you’d never willingly let your physical body be destroyed, no matter the claimed “benefits.” For most people today, the very thought of going through this device makes their hair rise and heartbeat race, at least a little bit. In their view of the world and themselves, it would subjectively feel like death. Even though evidence in this case (others have gone before you, with no apparent harm) argues strongly otherwise, our instinct still tells us to preserve ourselves, and not go. Reanimators trust that instinct, and behave accordingly.

If you are presently willing to go through the transporter under these conditions, gaining the benefit of instantaneous travel, while acknowledging the risk that you may in fact be killing yourself each time, you are likely an uploader. Uploaders say that as long as being transported doesn’t feel like being killed or changed either during the process or when they wake up on the other side, whether “killing” is actually occurring during molecular disassembly is an irrelevant philosophical distinction. Uploaders would see their instinct in this case, evolved in a time when humans were only biological, as simply wrong. They may flinch, dig their nails, or grit their teeth the first few times they are being disassembled, but they will go. Over time, they know their instinctual fear will subside, as with any low-risk but still potentially catastrophic activity, like flying, and their mind will learn to manage their fears.

The teleportation process itself wouldn’t even have to be fully painless, for uploaders to use it daily. After all, we all suffer regular small pains today, in various procedures, in order to get personal or social benefits. What matters most in such a process is the net result — what you can do and feel on the other side, versus what you can do, here and now, and the pain and cost of changing from your current state to a different state of being. These are the same questions we face when we think about brain preservation vs. not preserving, at the end of our biological lives. Both make sense, for different folks, and depend on our expectations of net result.

If you aren’t sure, or if you suspect that even after the successful transporter experiences of others, your copy could easily still have subtle but important “pattern insufficiencies”, defects in the copy that might only be discovered years later, at which point you might feel grief for the permanent loss of those particular parts of yourself, you’re probably an uncertain. Alternatively, if you expect you’d have continuing high levels of fear and doubt each time you transported, like that subset of folks who remain abnormally fearful of flying even after many flights, you are also still in the uncertain camp.

What about you? Would you currently go? Would you not go? Do you think you’d remain uncertain about the outcome, for yourself or others?

Consider that all three responses to this test are valid, from the point of view of members of each camp. If such a device were created, all three mental attitudes would be common, and all three would be socially reinforced as the right choice, by the members of each camp. So it should be obvious that each camp needs to learn to get along better, right?

The Three Camps in Social Media

Banner Graphic for reddit/r/futurology (2016), presently the largest futurist discussion platform on our planet.

As one might expect, whenever the topic of brain preservation comes up on social networks today, the comments among the positive responders (those who are either open to or attracted in some way to the idea) very often fall into endless discussions of the copy problem. We’ll ignore the much larger group of negative responders for now, as they aren’t even in the market for this choice at present.

The copy problem is an unresolved problem in philosophy of identity, perhaps as difficult today as topics like like consciousness, free will, the origin of life, and the purpose of the universe. We approach these and other puzzles with today’s imperfect science and evidence, and our personal beliefs, intuitions and argument.

Folks on each side of the issue argue incessantly about whether an upload would really be “you”. But one obvious thing we can say today is that over time, these folks predictably sort themselves into these three camps.

In our experience, most positive responders who are new to the idea of brain preservation, whether young or old, are default reanimators (Camp 1). And because so little of the science, evidence, and arguments around the choice has been discussed in society to date, and just as importantly, since so few people have made the brain preservation choice so far, most people are still new to the idea, even if they’ve heard it in the media several times before.

Thus reanimators (Camp 1), and most of those who are new to these ideas, tend to start with a strong instinctual and emotional bias against the idea of coming back as a “copy.” Thus they think and feel that uploading (Camp 2) would be death. They are often not uncertain (Camp 3) about their position. Some even like to call others foolish for making the uploading choice. That behavior should change. We all need to get along.

A distinct minority of the positive responders in these discussions, are either uploaders or uncertains. But while they are each minorities, both Camps 2 and 3 can be quite persuasive when they use logic and evidence to argue their case. Unfortunately, some uploaders also enflame these discussions, calling reanimators ignorant or biased. Uncertains sometimes scoff at Camps 1 and 2 as living in fantasy worlds, with no rational arguments, which is also unhelpful.

For reanimators, a copy is not the original. It’s obviously something else. For uploaders, we are all copies of our former selves. They note that life is constantly copying our body’s essential patterns, moment-by-moment, into new molecules, just to stay alive. Uncertains say that copy problem discussions are all just unprovable speculation at this point. Some even claim the problem is metaphysics, meaning we may never know an answer, and can only make ever-finer observations of the copies. What’s more, even if the copy differs subtly from the original, it isn’t clear how much difference people would find acceptable before they stop transporting (uploading). That decision will differ for different people, and is a very personal one.

Things get even weirder when the discussion turns to making multiple copies of individual minds. Uploaders tend to see this as an advantage, something many future minds may want. Just as biology occasionally creates initially-identical twins, which then go on to live unique lives, technology may one day able to create initially-identical minds, which will then immediately start to “fork” into increasingly-divergent identities. Think of this as a much stronger version of the forking we do in our own heads when spatially distinct neural nets upload the same information and then start arguing about it, sometimes for the rest of our lives.

We might even merge some or all of our forked minds later again, if we want, just as we sometimes resolve those internal arguments we have, and as even multiple personalities in one individual can sometimes be reassociated into one personality via psychotherapy. Reanimators and uncertains are often disbelieving or skeptical of such forking and reassociation claims, and they may also question the value or ethics of such a process.

One more weirdness emerges when we start talking about the attitude of copied minds toward death. Some uploaders argue that for backed-up uploads, death would become a minor annoyance, not the major traumatic event it often is today. Certainly no copy would willingly kill itself, unless there was some benefit that resulted, as in the Transporter Test. Sentient minds want to survive.

But notice that for uploaders, the concept of “survival” itself begins to have a different meaning, the better our mental patterns are backed up. Unwilling or accidental deaths might cause little subjective violence to an upload that knew it had a copy that would carry on. The copied mind might be annoyed by a forced or accidental death, the way we get annoyed when our backed-up hard drive crashes today, and know we’ll now be wasting time restoring the copy. Thus an uploaded human, or a biological human with a good backup, might no longer feel sadness or loss as they were dying, if they knew they had a safe and recent copy “in the cloud.”

This Zen attitude toward death also suggests that uploaders might do many more risky but potentially useful things during their lives, with various copies of themselves. Because they’d be so mentally faster, more flexible, more durable, and more willing to push the edge, an uploaded humanity might be the future of life’s creative and experimental activities on Earth. That’s a pretty big reward, if their perspective turns out to be true.

Reanimators, by contrast, would never take this philosophical position. They just don’t buy the arguments, or even if they grant them, they believe they would never change their instincts to feel this way. Uncertains consider both scenarios and their probabilities to be either unknown or unknowable.

What can we say about the future of debates among the three camps?

First, it is easy to predict that ongoing exposure to the advancing science, evidence, and arguments around these topics will keep growing the number of positive responders to the idea of brain preservation. So that’s an obvious future, even if the percentage growth is much harder to forecast.

Second, we can also predict that the debate will move more people out of the default reanimation camp and into both the uploading and uncertain camps, the more we become aware of the informational nature of ourselves. This is perhaps a less obvious future. If this happens, the three camps may become a bit more even in their percentages in coming years, which should make future debates even more interesting. Uploaders won’t be written off as an unimportant minority, the way they sometimes are today.

Furthermore, we think the greater diversity and depth of thinking that will result from these ongoing debates is a very worthy social goal. Discussions between the three camps and every other group in society are worthwhile, not idle speculation, and they help us better understand ourselves. In the process, we can all learn to better recognize those times when our instinctual judgments about ourselves and the world are cognitive biases, incorrect ways of thinking and feeling that falsely make others wrong, or that prevent us from seeing the real future.

Finally, we believe that humanity is at the beginning of a massive social education process on the worthiness of the brain preservation choice. This process will likely take many years to complete. Being patient, evidence-based, compassionate, and yet true to our convictions when discussing this choice, we can each do our part in that social re-education, and move the world to better ways of thinking.

From Abstract Philosophy to Concrete Choice

I bet you know what’s coming next. The transporter test is no mere philosophical exercise, but a real choice you have today, involving potentially saving your life and the lives of your friends and loved ones, and returning them to the world later. That’s because the first half of this transporter exists today. It’s called brain preservation. It has the potential to take you to a future world. Or at least transport all the matter and patterns that neuroscientists presently associate with your memory, and very likely also your full personality and self, to a future time. The quality of preservation needed for this transporter to work well, and the lowest cost at which this quality can be provided, are the big unknown questions at this point. That’s why “validation” of preservation techniques is the most important issue the BPF is doing its small part to help with, a challenge that gets more achievable as neuroscience advances a bit more every year.

So the stakes are high around this choice, as high as they could possibly be, for each of us who currently have the means and privilege to consider this choice. Even so, we need to recognize that just as with the transporter test, each of these camps will have different visions and preferences for how they might come back in the future. All three camps beliefs and preferences (“I want to come back in biology,” “I’d rather come back in technology,” or “I have no idea, I’ll leave it to the future to figure out”) and the many reasons that any of us might decide not to do brain preservation either today or in the future, should be respected. Humans love to create diversity of choice and lifestyle, and there’s no need to call others wrong for their choices.

Since each of these camps has different expectations regarding their future revival, each camp has different preferences today, with respect to the physical procedures of brain preservation. As we’ll see in our next post, there are now three evidence-backed preservation technologies that one might choose for oneself and one’s loved ones at the end of life. At present only one option, vitrification cryonics, is commercially available. But the second two options, aldehyde-stabilized cryonics and chemical brain preservation, are under development. Ideally, all three options will be available in the mid-term future. The commercial emergence of all three of these preservation choices in coming years may bring much-needed diversity and competition to field that has long had only one option available to all three camps.

Thanks for reading, and for any feedback you’d like to share.

Like to know more?

I am grateful to the following BPF Fellows, each co-authors of this post:
Michael Cerullo, M.D.
Author, The Ethics of Chemical Brain Preservation (2015).
Keith Wiley, Ph.D.
Author, A Taxonomy and Metaphysics of Mind-Uploading (2014).

John Smart is CEO of Foresight University, author of The Foresight Guide, and co-founder, with Ken Hayworth, Ph.D., of the Brain Preservation Foundation. Find him on Medium, Twitter, LinkedIn, or YouTube.

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