Why did ALL non-avian dinosaurs go extint, but not all reptiles?

Quite famously dinosaurs were the dominant clade on Earth for over 150 million years, which for animal species is a very, very long time (for example hominids have "only" existed for about 6 million years, apes even less than that, humans even less). Also quite famously not only did all non-avian dinosaurs go extinct, but they all did so in a quite short period of time in a single mass extinction event. (And yes, they did indeed go extinct surprisingly quickly all at once. In mere years, perhaps even less. It was absolutely catastrophic and devastating.)

A curious mind could ask: How come all of the thousands and thousands non-avian dinosaur species that existed 65 million years ago went extinct, while many reptile species survived (alongside many mammal species, etc)? This completely regardless of dinosaur type, size, eating habits, etc.

Many people often throw the guess that it was because of their sheer size, but they forget that there were literally hundreds if not thousands of dinosaur species that were very small, the size of a dog, some even the size of a chicken. Why did all of them go extinct too, while much bigger reptiles (such as crocodiles) survived? Likewise they went extinct regardless of whether they were carnivorous, herbivorous or omnivorous. It was definitely not about their size nor their diet.

Many conspiracy theorists, some young-earth creationists, and many other wackos, use this apparent paradox to claim that dinosaurs didn't actually exist, or similar silly theories (rather than actually trying to find out the reason.)

But it is indeed curious: Why did all of them (except the avian ones) go extinct? Every single species of dinosaur, without fail. This, while at the same time, many species of reptiles survived. How come the extinction event was this thorough but selective?

As you might surmise, the answer lies in how dinosaurs were different from other reptiles (and eg. mammals). While they are cladistically classified as "reptiles" that doesn't mean that they were identical to other reptiles.

While the full set of reasons why they went extinct is quite large and varied, ie. it was a combination of many things, their physical characteristics, their physiology, was a very crucial one. The characteristics that made them different from other reptiles (especially those that survived).

You see, most reptiles are cold-blooded, while dinosaurs (all of them) were mesothermic. They also quite crucially had a much higher metabolism rate than most other reptiles. (And this is, in fact, why so many dinosaur species were so incredibly fast-running apex predators, especially many of the theropod species.)

This meant, among other things, that they needed significantly more food than their non-dinosaur reptile cousins (most of which could go literally weeks without eating anything). And this is one of the crucial key characteristics that made them different from most other reptiles.

In a way, dinosaurs were extremely adapted and specialized for the Mesozoic environment: They were big, they were fast, they were strong, they were apex predators, they were capable of defending themselves (even if herbivorous). They were the pinnacles of the Mesozoic era. The top tier.

The problem with this is that this strength was also their weakness: The Cretaceous–Paleogene extinction event suddenly, completely and radically changed the environment in a way that made it completely unsuitable for the highly-specialized dinosaurs. Suddenly their fast metabolism became a liability rather than an asset. Suddenly their need for a constant supply of food became a deadly defect rather than a strength.

Of course this isn't the only reason why they suddenly became incapable of surviving in the changed environment (another one is that regardless of their fast metabolism, their reproduction cycle was really slow, which was also a liability after the extinction event), but it was one of the most crucial ones.

This explains why they all died, while many other reptiles survived: Those other reptiles had slower metabolisms, were cold-blooded, and did not require such a constant supply of food to survive. They also usually reproduced much faster.

From the dinosaurs, only birds survived, but that's because they could compensate their now-weaknesses with their unique ability of flight (and small size, feathers, and a relatively fast reproductive cycle).

The question of why all non-avian dinosaurs went extinct all of a sudden is actually a very interesting one. Too bad that many conspiracy theorists don't care. 

The Shroud of Turin is ridiculously and obviously fake

I find it a bit curious how seriously so many people, even many atheists and skeptics, take the Shroud of Turin. Obviously most skeptics don't believe that it represents the body of Jesus himself and instead it originates from the Middle Ages (with carbon dating putting it somewhere in the 1300's, give or take), but they still don't seem to have much problem or skepticism in believing that it's likely a real impression of a real body (although, to be fair, there are also those who believe that it's just a hand-made painting and nothing more.)

It's actually a bit unbelievable how many people believe that it's the actual real impression of a real human body, given how obviously fake it is.

As a side note (and somewhat unrelated to how obviously fake it is), the vast, vast majority of people don't even know what the entire cloth looks like and how the impressions are placed on it. The entire original cloth looks like this:

If it was covering a body, it would mean that the body was laying on top of it on one half, and then it was folded over his head on top of him, like a blanket.

Most people think that the shroud was actually wrapping the body, but it's quite obvious that it wasn't. Even if it was covering a real body, it was just laying flat on a surface, like a sheet, with the body on top of it, and the upper half folded over to cover it, like a blanket. The shroud was not wrapping the body.

This is, rather obviously, not under dispute, as it's extremely obvious from the shroud. It's just curious how few people know and understand this, and instead assume that the cloth was wrapping the body tightly.

Likewise few people are wondering what exactly are the human-shaped stains made of. They rather obviously assume it's blood, but they don't stop to think how unrealistic that is. It would mean that the body would have been completely covered, from head to toe, all of it, in fresh blood, at least fresh enough to permanently stain the cloth.

Believers in the authenticity of the cloth, and Jesus himself, never stop to think how impossible that is. According to the scriptures Jesus was kept on the cross after his death for several hours at minimum. Blood coagulates quite quickly and doesn't stay fresh for that long.

Also, at which point was this cloth used? Most people assume that it was probably used to wrap Jesus's body in the tomb. They forget that according to the narrative his body was washed before putting it in the tomb. Thus, even if we were to entertain the idea that this was used to wrap the body of the real Jesus, at which point did this happen? It would have been several hours after his death, after he had been taken down and his body transported somewhere else.

Analysis of the stain appear to strongly suggest that, at a very minimum, the original stains were enhanced and expanded using a mixture of red ochre and a gelatin medium, which was a common paint in the Middle Ages. While some experts dispute this, I think that it's pretty much certain.

But none of this makes the shroud "ridiculously and obviously fake". Even if it's from the medieval period rather than two thousand years ago, it could still be genuine in the sense that it was used to cover the real body of someone.

Let's examine more closely why it's ridiculously and obviously fake. In particular, let's examine the face:

This is a picture of the stains on the original cloth, and a digitally enhanced version of its negative, which emphasizes the details in the original.

Am I seriously expected to believe that a cloth placed on top of someone's face, said face covered in something (supposedly blood), is going to leave that many intricate details on the cloth? Eyelids perfectly lined, the sides of the nose perfectly lined and shaded, lips, moustache perfectly delineated, eyebrows and forehead perfectly shaded, cheeks perfectly delineated and shaded, and somehow long hair (apparently also soaked in blood?) leaving just the perfect impression on the cloth, all the way from the top of the head to the tips near the neck, not spread out, apparently not affected by gravity, no gaps, nothing? Are you seriously telling me that even the eyelashes of the closed eyes left a distinct impression in the cloth? That the gap between the bottom of the eyelids and the cheeks got so perfectly impressed into the cloth?

Also note the differences in shading, in how dark the stains are. The digitally enhanced image emphasizes this, but if you examine the original closely, you can see the different shades of darker and lighter areas there as well. Am I seriously supposed to believe that a cloth placed on top of a face (apparently soaked in blood for some reason) is going to leave these differently-shaded stains on the cloth, with for example the cheeks gently fading from darker to lighter, as if the face had been illuminated from above? Am I seriously supposed to believe that the nose has just the perfect shading, as if it had been illuminated from above and slightly from the right? Am I seriously supposed to believe that the underside of the eyebrows are perfectly shaded as if the face had been illuminated from above?

This is so obviously painted by hand that it isn't even funny.

The rest of the body isn't much better, although the face is the epitome of how obviously fake this is, because of all the minute tiny details that would absolutely not be that detailed if it had just been a sheet of cloth placed on top of a face covered in blood. You can even see individual fingers, and parts of the body that would not have been touched by the cloth if it had just been placed on top of it.

There are many other problems that can be pointed out as well, such as for example the curious fact that even though the entire body was supposedly covered in blood, there are literally zero signs of this blood dripping to the back part of the cloth. Apparently all this fresh blood, so fresh that it could paint the cloth, did not flow and drip to the part of the cloth that was under the body.

Curiously and funnily, the fact that the shroud includes the part that was under the body is a clear testament that the body was quite clearly not soaked in blood, or any other substance that would flow and drip onto that section that was supposedly under the body.

It is very likely that someone deliberately created the cloth. It might have been a deliberate hoax, or it might have been for genuine purposes, like a so-called death mask (assuming it was created from a real body and not a statue). It's quite clear that whoever created it painted the body with some paint and then put the cloth on top of it and pressed it against it in order to create the impressions, and then extremely likely retouched the end result to enhance the details.

Either way, it should be extremely obvious that it was a deliberate painting, even if it was based on a real body, not just a cloth placed on top of a dead body that just somehow miraculously happened to get such a perfect impression of the body.

And, rather obviously, given that it is quite clearly either a "death mask" of sorts, or some kind of deliberate hoax, it cannot be from the body of Jesus (assuming he even existed in the first place.) 

"Objective" vs "subjective" morality

Many Christian apologists argue that God's statutes (laid out in the Bible, of course) are "objective morality" and thus universally true and perfect, and they argue against "subjective morality" pretty much considering it ethically abhorrent (because, according to them, it would justify people doing whatever evil they want.)

There are many things wrong with this argument, and their very definitions of these concepts. Here are the two major ones:

Firstly, they don't seem to understand what "objective" means. When they talk about "objective morality" in this context, they seem to think that "objective" is something similar to a law of physics: In other words, something that's an absolute and inherent immutable feature of our reality, and is so completely regardless of us, something that would be true even if we (or any living being whatsoever) existed at all. A bit like the law of gravitation, or the law of electric charge: These exist in this universe completely regardless of anything, and are hard immutable characteristics of it, ie. they are laws of physics.

That's not what "objective" means. If you look at any dictionary definition, in this context "objective" means "not influenced by personal feelings, interpretations, or prejudice; based on facts; unbiased."

In other words, an "objective moral" is not something that's an inherent part of the properties of this universe that exists independently for us and is always the identically the same everywhere at all times regardless of anything. It's simply a moral that's not based on feelings, emotions and biased interpretations, but instead it's arguably based on unbiased interpretation of hard facts.

The thing is: Two different incompatible sets of morals can both be "objective", and there is no contradiction in this. "Objective" does not mean "universal", in other words, inherently and by necessity exactly the same for everybody, regardless of anything. "Objective" means that it's based on unbiased interpretation of facts rather than the result of personal feelings and subjective interpretations. Different things can be factually true for different cultures, for example based on their geographical location, geographic features, the environment, the local culture, and the history of the culture. For example, it can be factually true that the place suffers from yearly floods, and this may shape the moral code of the people living there. In a completely different place it may be factually true that they suffer from regular drought, and this also shapes the moral code of the people living there, and these two moral codes may be different and in some ways even incompatible, because they apply to that particular people in that particular place. Both can be a fully objective set of morals without any subjectivity: It's just that those morals are dictated by different facts caused by the different circumstances.

"Objective morality" is not by necessity universal, the exact same everywhere regardless of anything. Different (and even incompatible) sets of morals can both be "objective" at the same time. There is no contradiction here.

Secondly, these Christian apologists always contrast the two options at their most extreme: In other words, their argument is that either there is a strict set of objective morality that's universal, strict, immutable and the same for everybody, or alternatively there's "subjective morality" which, according to them, means that anybody can do whatever they want without any limits whatsoever. That's it. Those are the two only options. There's nothing in between.

This is a false dichotomy.

Morality does not work that way. In actual reality there are degrees of objectiveness / subjectiveness when it comes to ethics and morality. It's a gradation. It's not a situation where there are only two possibilities and, particularly, those two options are the absolute extremes and nothing else.

This is the reason why, for example, most laws in most countries dictate a range of possible punishments for crimes. While "guilty" vs "not guilty" may be a true dichotomy when it comes to the legal system, the punishment if found guilty is usually a gradation, with minimum and maximum sentences. The actual sentence is chosen according to the severity of the crime. In other words, how wrong and harmful the action was. It may have been objectively wrong, but its severity may vary. There aren't only two extreme options: Either let the accused to free, or always inflict maximum punishment.

"Objective morality", as these Christians wrongly define it, would require only those two options to be viable: Either not guilty, or maximum punishment. Nothing in between.

Even in non-legal settings morality is a gradation, not just a dichotomy of two extremes. There are always degrees of how "right" or "wrong" something is. For example pushing someone may be very wrong in some circumstances, a bit reproachable but not completely despicable in others, and completely acceptable and even a good action in others (for example if it saves someone's life.) Context always matters.

And yes, there is a lot of morality that's up to subjective feelings and interpretations. It can be considered highly improper to exhibit bad manners and bad behavior in certain situations, but how "wrong" it is, that's often up to personal opinion and customs. There are genuinely things where the "wrongness" of some action is very much up to personal opinion and personal preferences, and thus being highly subjective.

With most actions, however, the degree of "objectiveness" of how "wrong" they are is much more of a gradation. The "wrongness" of some actions are more up to opinion, with other actions it's more objective, and there are enough things that humans can do to fill up the entire line from one end to the other. The line where actions become so wrong that even laws have to be passed to criminalize them is, perhaps ironically, a mix of objectivity and, to certain degree, also subjectivity, depending a bit on the local culture and customs. And that is, as mentioned before, where the severity of the punishment kicks in, with "minimum" and "maximum" sentences that can vary quite wildly.

The "Kent Hovind"-style challenge

Kent Hovind has for several decades been rather infamous for not only being a Christian young-earth creationist activist, who has made an entire video series of presentations about his wacky theories as well as making thousands of YouTube videos where he repeats the same things over and over, but more prominently because of his egregiously smug and condescending attitude towards "atheists" and anybody who disagrees with him.

Say what you like about apologists like William Lane Craig (who is the King of Sophistry, to the extreme degree), Ken Ham and others like them, at least they know how to maintain a modicum of politeness and good manners, regardless of how wrong what they say may be. Not Kent Hovind: He is extremely smug, condescending and egregiously patronizing when talking about "atheists" and their arguments. So very Christian of him.

Anyway, he is also somewhat famous for his "evolution challenge": At least in the past (I don't know if currently) he promised to pay 10 thousand dollars (or whatever the sum was) to anybody who can give him any "proof of evolution".

This challenge is very easy and safe for him to present. That's because it has two main problems:

Firstly, a bit of a more minor problem is that he has never specified (and quite deliberately so) the conditions for the "proofs" presented to him. He has never explained what he will accept as valid "proof" and what he won't.

The problem with this is that it leaves the judging of the validity of the presented proof completely open, up to the whims of whoever is judging, with no clearly defined parameters under which such a proof will be considered valid. It will be completely up to the whims of whoever is judging.

Which brings up to the second and absolutely major problem in the challenge:

Who will be judging whether a presented "proof" is valid, and thus earns the 10 thousand dollars? Well, what do you know, Kent Hovind himself, of course.

Indeed, he himself is the only and sole person judging the validity of the presented "proof", and his word is the final verdict, regardless of anything. Thus, he simply has to reject the proof, regardless of what it is, and what do you know, he doesn't need to pay. That's it. It's that simple. He doesn't even need to present any counter-argument or explain why he is rejecting the proof: He can simply reject it, and he doesn't have to pay, under his own self-imposed rules of the "challenge".

And, indeed, he has a stock answer to almost every single "proof" presented to him, which he almost always gives as a stock response: "That's not evolution."

It doesn't matter what the presented proof is, he just has to answer "that's not evolution", and he doesn't need to pay. Under his perspective the "challenge" was once again lost by the "evolutionist". Obviously he can then go ahead and boast about how his "challenge" has never been broken, and how "nobody can present a single proof of evolution." Which he does constantly.

Of course he never talks about the fact that he himself is the only and sole judge deciding whether his "challenge" has been broken or not.

Unsurprisingly, he is not the only one engaging in this exact type of easy and safe "challenge". Many other creationists, conspiracy theorists, flat earthers, and other such people have also presented the exact same "challenge": Provide proof that their claims are false and you earn X thousand dollars. Problem is, of course, that it's the issuer of the challenge who all alone will be the sole judge of whether the proof is valid or not. Thus, the challenge is very safe to issue: The challenger will never have to pay up because he can just dismiss any proof presented to him.

And then he can go ahead and boast about how nobody can prove he is wrong and nobody has ever won the challenge. 

Why the Manhattan "eruv" wire makes no sense

Orthodox Judaism has a huge amount of rules that are not directly found in the Torah or the rest of the Hebrew Bible (ie. "Old Testament").

As an example: In Orthodox Judaism you must make absolutely certain that you never, ever mix meat and milk. Not even a single molecule must be mixed. The strongest adherents of Judaism go so far as having divided their kitchen into two parts, where nothing crosses the line from one part to the other: Cookware, utensils, dishes, raw ingredients... Each half has its own set of them, and they must never, ever cross to the other side. Even the not-so-strong adherents will have at least some measures to make sure that no molecule of milk ever touches a molecule of meat by, at a minimum, never using the two ingredients at the same time and judiciously washing all cookware, utensils and dishes in between (although most prefer to just have two separate sets of them.)

Nothing like this is mandated in the Hebrew Bible, though (nor are there any mentions or examples of people doing anything like this). In fact, there is no commandment against eating meat and milk at the same time. Not even goat meat and goat milk at the same time. The only thing that's prohibited is boiling goat in its mother's milk. (This is a rather strange commandment, and some have hypothesized that it's actually metaphorical, and the people of the time would have understood what it actually meant. However, that's not important in this blog post.)

So if the prohibition is so specific, why go to such lengths and create a huge amount of rules that seem completely overblown and extreme?

The basic idea is that all these additional rules and mandates are there to protect a person from accidentally breaking a commandment. Rabbis themselves call this "building a fence around the commandments": In other words, follow rules that keep you as far as possible from even accidentally breaking a commandment. After all, if you have milk and meat in the same dinner, there is the remote possibility that the meat happens to contain goat and the milk happens to be from its mother, and if the meat is hot, it may end up being "boiled" in that milk, no matter how briefly. No matter how extraordinarily remote that possibility may be, it's better to err on the side of caution: Don't let even the remote chance become reality!

In other words, all these extra rules have the principle of "it's better to keep as far away from the line (of breaking a commandment) as possible, than to take any chances." No measure is too extreme to protect you from accidentally crossing that line. If using separate kitchen utensils protects you from even accidental breaking of the law, it's well worth it.

And, of course, this is only one example of literally thousands.

Naturally what can and can't be done has sparked endless debates among Jewish scholars and Rabbis over the centuries.

One of the topics that has sparked probably the most amount of discussion is what counts as "work", which is forbidden from being done on the Sabbath?

Obviously doing anything related to your job is clearly "work". But can something else also be considered such? What about doing chores at home, such as repairing something that's broken? Is that "work" that's forbidden during Sabbath? Again: Better to err on the side of caution and consider it such. Thus, you cannot repair anything during the Sabbath.

This "protective fence" around the prohibition of doing "work" during the Sabbath can sometimes go to rather ridiculous extremes. For example, a very common interpretation is that just switching on a light is "work", and thus shouldn't be done during a Sabbath. (The train of thought is that historically lighting up something required starting a fire, which can be quite exerting and requires tools and skill. Clearly it's work! Not so much different than eg. repairing something. Thus lighting a fire during Sabbath is best avoided. The modern equivalent is flipping a light switch to turn on the lights: Same thing, just a more modern version. Thus, once again, better to err on the side of caution: You shouldn't be switching lights during Sabbath.)

Carrying heavy loads, even if it's just inside your home, is also quite clearly considered work, as it's physically exerting, and it goes against the principle of the Sabbath being a day of rest.

But what about carrying very lightweight things? Can you carry your keys in a pocket, for example? Is that work or not? What if you have to carry something lightweight due to necessity, such as bringing food to a sick family member? Is that work?

After much deliberation the scholars and Rabbis came to the decision that carrying relatively light weights is allowed during the Sabbath, but only in your home. You must not carry anything further than that.

Of course the next question became: What exactly constitutes "your home"? Is it just the space confined inside walls? What about a patio, or a garden? Are you allowed to exit the door of your house carrying something?

A concession was made: Your property is your home, and that can include not just the house but also the immediate land around it, such as a patio or a garden.

However, in order to know where exactly the line is, it was decided that every Orthodox Jew who owns a home with property around it should clearly mark where the line is that must not be crossed while carrying something. This is marked with a so-called "eruv", which is a wire or string for this exact purpose: It marks the limits of the area where you can carry light loads, and must not be crossed.

And this is where the "abuse" of this allowance started happening. For example, if the properties of two neighbors were side-by-side, some of them would use a joint "eruv" wire that went around both properties, allowing them to carry stuff from one home to the other. After all, they didn't need to cross the line because the line was surrounding the joint property.

What if a third neighbor wanted to join the party? Well, extend the "eruv" to cover his property as well! Now all three could travel to any of the other two homes, carrying stuff, as no wire was being crossed.

And, thus, we get to the absolutely ridiculous end point of all this gameplay: The "Manhattan eruv wire". Which is an "eruv" wire that surrounds a good chunk of Manhattan. An absolutely humongous area.

Orthodox Jews who live within this area take this to mean that they can carry stuff within that huge area without worry. Which, rather obviously, goes against the original idea of limiting this area as much as possible.

In light of the other stuff about the "kosher" rules, which are designed to keep the faithful as protected as possible from breaking any commandments, going to absolute extremes to make sure of that, this ridiculous "Manhattan eruv" is certainly going to an absolute extreme... in the opposite direction! In other words, towards the line of what constitutes breaking the Sabbath and what doesn't. It's the exact opposite of the idea of keeping oneself as far as possible from breaching that line.

Which is why it just doesn't make any sense.

The actual reason O'Reilly's "tide goes in/out" argument doesn't work

There's a very memetic video clip of Bill O'Reilly, who had invited an atheist activist, David Silverman, to his show in order to have a discussion about religion vs. atheism, where O'Reilly quite (in)famously argued:

"I'll tell you why it's not a scam. In my opinion, all right? Tide goes in, tide goes out. Never a miscommunication. You can't explain that."

He became quite a laughing stock because of his argument primarily because rather obviously we know perfectly well how and why tides work, why they have the timing that they do, and we have known this for literally centuries.

However, most people miss the most important reason why it's an invalid argument. The most important reason is not that he is incorrect in his assertion that "you can't explain that". The most important reason is the implication, the deduction based on that.

Let's assume for the sake of the argument that science, humanity in general, had absolutely no idea why and how tides work. Complete mystery. We have studied and studied it for centuries, and to this day we have absolutely no idea. Science calls it "the great tide anomaly" (similarly to "the Pioneer anomaly" and "the flyby anomaly"). Let's assume that O'Reilly was 100% correct in that "you can't explain that."

What can we deduce from this?

Absolutely nothing, that's what. The only thing that we can deduce from it is that we just don't know. It's a mystery. Our science is not advanced enough to have any explanation. But that's it. That's literally the only thing we can deduce from it.

The main point is that "you can't explain that" is not a valid argument for the existence of God. Or any gods. Or even the supernatural. It's just an unknown. (This kind of fallacious argument actually has a name: Argumentum ad ignorantiam. In other words, "argument from ignorance", or more unambiguously and precisely, "argument from not knowing", ie. "argument from an unknown.")

We could perfectly well substitute the "tides" in O'Reilly's argument with something else that we genuinely don't yet understand. For example:

"I'll tell you why it's not a scam. In my opinion, all right? Mass bends space-time, causing gravity. Never a miscommunication, always works the same way. You can't explain that."

In this case the "you can't explain that" is actually correct. However, we still can't deduce anything from it. It's just that: An unknown. We don't have the technical details behind the phenomenon. We just don't know. But that's all we can deduce.

If I were a Catholic, I would probably be a Sedevacantist

"Sedevacantism" is a fringe movement within Catholicism, held by some Catholics, including some priests, that posits that all the recent popes are heretics and, thus, are not genuine God-appointed heads of the Catholic Church and, thus, the position of the Pope, ie. the Holy See, has been vacant for several decades, with no genuine God-approved Pope holding the office.

Which Pope was the last legitimate one depends a bit on the sedevacantist, but the most general consensus is that it was Pius XII (who was Pope from 1939 to 1958), and that the first non-legitimate heretical pope was the next one, John XXIII, under whose papacy the famous (or rather, infamous, from the perspective of sedevacantists) Second Vatican Council was held.

(There's probably no consensus on whether John XXIII started as a legitimate Pope and later became a heretic, or whether he was a heretic from the start, but that doesn't really make a lot of difference. Even if he was legitimate at first, in the sedevacantist view he lost his claim to the Holy See when he committed heresy, and thus stopped being the legitimate Pope.)

Sedevacantists do not deny the teachings of the Catholic Church nor the authority of the Pope (as long as he is the legitimate one). On the contrary, they tend to be extreme hard-line Catholics who very strongly believe in traditional Catholicism, and that the Catholic Church, with all of its teachings, has been the True Church of Christianity for two thousand years.

However, they deny the validity of many of the decrees of the Second Vatican Council, considering most of it heretical, and with it likewise all the subsequent popes who have accepted those decrees to likewise be heretics and thus not true Popes.

The Second Vatican Council was one of the most notorious ecumenical councils of the Catholic Church, generating fundamental sweeping changes to many of the official positions and teachings of the Church. In many ways this council made the Catholic Church significantly more "liberal" in its views, away from the very strict hard-line positions held previously. Some of the most significant changes were:

• Catholic Mass had been held in Ecclesiastic Latin for over a thousand years. This council freed all priests to allow them to hold Mass in their local language.
• The position that the Catholic Church is the only true Church of God was softened and replaced with a more ecumenical view where Catholicism acknowledges that other denominations may also hold some validity in the eyes of God.
• The council declared that not all Jews were responsible for the execution of Jesus.
• It also declared that all people have religious freedom, the fundamental right to choose which religion they follow (in other words, the Catholic Church cannot force nor coerce people into following Catholicism.)
• The position on studying the Bible by laypeople was changed: While previously the Church discouraged laypeople from studying the Bible without guidance and supervision from a priest, now the position was reversed and, on the contrary, laypeople were encouraged to do read the Bible even if there is no priest present.
• And related to that, the approach to scriptural interpretation was changed, encouraging taking into account the historical and cultural context of when the scriptures were written, when interpreting their meaning. (In other words, a more or less subtle hint that "not everything written should be taken literally, as if it applied in the exact same way to the modern world. Context matters.")
• The council somewhat de-emphasized the supreme authority of the Pope in all matters concerning the Church, and increased the role of bishops in those matters. (In other words, bishops became more free to make decisions without necessarily having to seek approval from the Vatican for every little thing.)
• Several changes were made to liturgies and church paraphernalia. 

At face value most of those changes seem positive. And, in fact, the Second Vatican Council was organized precisely because the pope of the time, John XXIII, felt that the Church was in need of such reforms. He felt that the animosity between the Catholic Church and other denominations had to end, as well as many other sweeping changes to make the Church more "people-friendly".

Sedevacantists, however, argue that most of those changes, and the entire motivation behind the council, were motivated by secular ideology, secular politics, and secular movements, rather than by God. They argue that John XXIII was not inspired by God to initiate this kind of radical reform, but by secular politics (and, thus, ultimately, Satan himself.)

After all, what is more likely, that the Catholic Church was completely wrong on those issues for almost two thousand years and only now, after all this time, and coincidentally alongside the rest of the world, decided to reveal the "actual truth" about those matters, or is it more likely that the Pope was inspired by secular politics rather than God?

Why would God wait for almost two thousand years, allowing the Church to have the wrong teachings and positions, before revealing the actual truth? And what a coincidence that this actual truth was revealed at the same time that the rest of the world was moving towards more liberal politics. Did God just come to the Pope and tell him "hey, you know what? Yeah, those secular philosophers, politicians and activists are actually right. Oops, my bad. I suppose we were both wrong. You'd better reform the Church."

Sedevacantists consider several of those changes to the official teaching and positions of the Church to be heretical, as they contradict the official positions held by the Church for almost two thousand years. And, consequently, they consider any pope who accepts those heretical views to be a heretic himself and, thus, not an actual legit valid Pope. Since none of the subsequent popes has denounced those reforms, they have all been heretics, and thus the Holy See has been vacant since that council.