Lion IRC, this is a reply to your "dogmatic" claim.
The information I found in support of the afterlife consists in claims of near death experiences and out of body experiences, plus religious claims and philosophical arguments. The arguments are really poor, and the empirical evidence does very little to support the claim, so it barely raises its probability. On the other hand, the evidence against the afterlife is overwhelming:
First, I see that there are movies, TV shows and generally works of fiction in which the evidence for the afterlife is indeed very strong (when needed, modified to avoid continuity problems, which we may do in order to consider a hypothetical scenario). For example, there are ghosts that appear to some of the main characters – or to all – and who communicate real information, or move things, possess people, and so on. Clearly, that’s a lot of evidence. There could be counter-evidence within the stories, but at least, a lot of things are found that support strongly an afterlife. If I were to observe that in the real world, I would definitely give an afterlife a far higher probability than I do. But I do not see any of that at all. What I see is claims of “near death experiences” which do little in the way of supporting the afterlife.
Second, there are also movies, TV shows, etc., in which evidence of an afterlife might be weaker than the previous one, but still, there is good evidence that human consciousness goes on without attachment to a particular brain. For example, spells that make two people “swap bodies”, or something like that. Now, that’s of course not as good as the previous list, but it’s something suggesting an afterlife at least, and definitely would block the counter-evidence I will list below. But again, I see nothing of the sort in the real world.
Third, what I see is this: when humans suffers different damage to different parts of the brain, they lose some mental abilities, properties, etc. For example, old people often suffer serious degradation to their capacity to reason, form new memories, learn new things. Other brain injuries can cause memory loss – even massive memory loss -, as well as a loss of the capacity to form new memories. They can also cause (depending on the injury) a loss of the ability to speak, or – again – to reason. They can also result in the loss of pain or the capacity to feel it, or to fear, and so on. Of course, injuries to the brain also can cause the loss of the ability to process sensory input, resulting in blindness, loss of hearing, and so on.
Now, different sorts of damage to the brain – temporary like with certain drugs, or permanent – also cause specific changes in moods, in what a person wants to do, in how calm or angry they are, etc.
It did not have to be like that, by the way. I might have found that when the brain is damaged – blow to the head, aging, disease -, the mind loses the ability to control it, perhaps sensory information, etc., but without losing anything else, certainly not consciousness, but also not things like the ability to reason, or fear, or memories, or any of the above. And of course, I could have found that people swap bodies with some spells. But no, that’s not remotely what I found.
Given the above, once all of the brain is destroyed, I reckon that no person is left – it’s all gone.
But what about phenomenal consciousness?
However, that is not left, either. There are excellent reasons to think that’s gone too. For example, we can see that some brain injuries – easily, a blow to the head – result in loss of consciousness, even if in those cases temporary. Destroy the whole brain, and it’s pretty obvious that nothing is left, especially given the rest of the above evidence.
Moreover, that’s not really the point: if some sort of phenomenal consciousness were left, there would still be no afterlife, since the person would have ceased to exist, and what would remain in that scenario would be something else, but not that person – nor, for that matter, a person at all.
This is not an argument against panpsychism, by the way. Even if, say, after a human dies, each of the gazillion particles left has some tiny part of mind, a phenomenal consciousness of sorts, that is no afterlife of course.
So, in short, there is no afterlife – human afterlife, that is, but the same holds for all other animals of course, even if some of the pieces of evidence are somewhat less direct in such cases.
Of course, it does not logically follow from any of the above that there is no afterlife. But for that matter, it does not follow from any piece of information at my disposal that, say, the Moon Landing ever happened, or that World War I happened, or that humans and fruit flies have a common ancestor, or that the Moon will still be orbiting the Earth next month, or that...well, anything about the world around me. Yet I know all of those things and many others, so clearly the fact that it does not follow from the information at my disposal would not be a serious objection.
I have encountered another, puzzling objection, which says that all of the things I mention only say that damage to the brain during life damages or affects the mind, but it says nothing about what happens after death. That is a confused objection. Of course, if I want to make an assessment about what will happen to a human mind, I have to look at the information that is available and make an assessment based on it. And of course, I might well have found good evidence of an afterlife and no counter-evidence (see examples above), but that is not what I found.
Now, of course, someone might come up with a specific description of an afterlife that is consistent and immune to the above: for example, one might describe a scenario in which a human mind is gradually or quickly deteriorating with age and disease, etc. - as it really happens – and then after the whole brain is destroyed, consciousness continues, and it’s the same consciousness not another one – e. g., the “body swap” happens only after death, and the person goes to an immortal body or whatever. However, if someone includes all of that in their hypothesis, they make it extremely improbable just as first, rather than after considering the evidence. For that matter, a defense attorney in a criminal case might say that even after the prosecutor presented all sorts of pieces of evidence, she has provided not even a tiny speck of evidence against the hypothesis that his client was framed by a powerful superintelligent extraterrestrial artificial intelligence that wanted to plant exactly the pieces of evidence found by the prosecutor, for such-and-such reasons (reasons the defense attorney can consistently make up). Well, if the defense attorney comes up with a sufficiently smart story, sure, the defense attorney has failed to provide evidence against that hypothesis. But that of course in no way prevents her from establishing the guilt of the defendant beyond a reasonable doubt.
In short, on the basis of the above evidence – plus specific debunking of specific religions when needed, but that would be beyond the scope of this short piece -, I reckon the afterlife does not exist – and further, I reckon I know that the afterlife does not exist.
