Fanghur

If a tree falls in a forest, and there is no one around, is it a tree? Badly mangling a quote of Bishop Berkeley which he never actually said in the first place.

 

You seem to be positing a toy universe which by definition contains everything, everyone and everything, which we are commenting on from our universe which also by definition contains everything, everyone, and everytime; yet you find the idea of a solipsism absurd - surely the only way your toy universe could exist is purely within one's own mind? What is ontology without the presumption of a mind to study the nature of being?

I quite honestly have no idea what you mean. A solipsist is someone who believes that they are the only thing in existence and everything else is just a figment of their imagination; ie. they believe that reality is subjective rather than objective. That is what I said was absurd.

That's because there's no such thing as a "logical absolute".

Fine, call it whatever you want then. Please address my objections rather than correcting my terminology.

Giving examples is not the same thing as defining. Guess what, they're just three forms of the same tautology. It's not even special, since all theorems are tautologies. Citing three equivalent forms of the same proposition in no way tells us what a "logical absolute" is.

Uninterpreted, logic is just manipulation of meaningless symbols. Given the standard interpretation, it's called "PROPOSITIONAL Calculus" and, as the name suggests, is about propositions. In a world with no minds, there are no propositions. So, yeah, logic doesn't exist if there are no minds.

 

The only thing logic has to do with is how ideas structurally relate to one another. That's it. Nothing more.

Yes, but what I am referring to the three logical absolutes are NOT logic. If no minds existed in the universe, what we know of as being a rock WOULD still be a rock, and would still not NOT be a rock. Therefore the ontological nature of the three tautologies would STILL apply to that universe. That is what the three tautologies are really saying. Otherwise you are essentially arguing for a solipsistic universe in which nothing exists unless someone observes it, and that is nonsense.

Read by posts again.There is no such thing as "logical absolutes".

First of all, what we refer to them as is unimportant. Even though Matt Slick's argument is completely flawed and fallacious, the term he coined for Identity, Non-Contradiction and Excluded Middle, namely 'logical absolutes', strikes me as an appropriate one, therefore I will use that term to save time.

I did read your posts; you said that the three 'logical absolutes' WERE conceptual and would NOT apply if no minds exist. Those assertions are both flawed and, in the case of the latter, nonsensical. It is true that our mathematical depiction of what those laws mean is conceptual; the statements "A = A", "A ≠ NOT A", and however one would mathematically depict the law of excluded middle, could not exist if we didn't create them. However, to say that because we have a concept in our minds of the three logical absolutes, the logical absolutes themselves are therefore conceptual is a logical fallacy. It is analogous to saying "I have a concept of an apple, therefore apples are conceptual". And to say that the logical absolutes ARE logic is another logical fallacy; it is saying "because logic is conceptual, the foundations upon which logic is based are also conceptual."

Now if this is not what you actually meant, then could you please clarify?

There's really no such thing as "laws of logic", but I think you're referring to three tautologies of bivalent sentential logic that people think are special for some reason. That would be pv~p, p=p, and ~(p&~p) (which is actually the same as pv~p).

 

Yes, they are.No, they wouldn't. Logics are invented, not discovered. Sentential logic is just the one that most closely approximates how thoughts relate to each other.

Wait a minute, let me get this straight. You're saying that, hypothetically, if the universe were exactly the way it is not but with the sole exception being that there were no minds, then the law of identity wouldn't apply? A rock in that mind-less universe wouldn't be a rock? That something wouldn't be what it is and not be what it isn't? That's absurd.

And just for the record, I am NOT arguing TAG and I think Matt Slick is a complete idiot. So please nobody get the impression that I'm doing that. The laws of identity, non-contradiction and excluded middle are NOT logic. They are the foundations which make logic possible. To say that because logic is conceptual therefore the 'logical absolutes' are also conceptual is a fallacy of division.

I know what the three laws of logic are and what they say. What I am not certain about is what they actually are; what is their nature? They aren't physical, they aren't material, they aren't conceptual because they would apply even if no minds existed, they are completely non-contingent on anything whatsoever because they would apply even to absolute nothingness if such a thing existed. So what would be a word that describes their nature? Does one even exist?

Does anyone know what exactly the three laws of logic - Identity, Non-Contradiction and Excluded Middle - are? To be clear, I am not referring to the statements, but rather the 'things' that those statements are referring to? What do you call something which all of existence is contingent on?

Is there even a word for what they are? Or does it fall into the category 'they simple ARE'?

What do you mean by net gravity?

 

But yes, when a star forms a black hole some of the star's initial mass will be lost in a supernova.

I was making an analogy wherein I compared the strength of a gravitational field to a chemical solution; in the original star (solution), the volume was incredibly large and so the gravity (chemical) was spread out over an extremely large area. When the star became a black hole, however, all that gravity became compressed into an infinitesimally small volume, and thus became far more 'concentrated'. Does this analogy make sense?

You are correct, that is not true. What makes them so strong is that you can get very, very, very close to the center of gravity. Since the strength of gravity is proportional to 1/r^2, where r is the distance from the center of gravity, you can see as the distance gets close to zero the strength blows up to infinity. If the Sun were to suddenly turn into a black hole, we'd still rotate around it all the same.

In practice, however, that does not actually happen though, correct? I mean, if for example we were able to somehow drill our way to the exact center of the Earth, the gravitational force wouldn't actually become infinite?

So then would it be fair to say that, if comparing space-time to an infinitely-elastic 'sheet', that a black hole would effectively be a tangent (i.e. tan(90) ) in that sheet? Or am I looking at this too literally?

I've been curious about this for a while, so correct me is I'm wrong. Black holes are often thought of as having more gravity than any other object in the universe, but a little while ago it occurred to me that this technically should not be true. Gravity is directly proportional to an object's mass If I'm not mistaken. And black holes are formed when a massive star goes supernova, effectively blowing a great proportion of its mass out into space. So with that in mind, wouldn't a black hole technically speaking have less net gravity than the original star did? To be sure that gravity would be far more 'concentrated' that that of the original star, but in terms of NET gravity possessed by the black hole, would it be fair to say that it has less gravity in that sense?

I'm currently reading a book by Jeremy Robinson of which the premise is that our solar system passes through some kind of massive interstellar cloud containing huge quantities of iron (in the form of snowflake-like flakes) that, to simplify a complicated story, hits the Earth and rains down like snow, becoming oxidized in the process, and ultimately removing all the oxygen in the lower atmosphere and wiping out millions of people by asphyxiation.

I was just wondering whether this idea even comes close to approximating being possible, or if along with some of Robinson's other ideas is pure fiction? Can anyone tell me?

Okay, clearly I did not explain myself well enough. I am not talking about simply taking an egg from one partner, fertilizing it via artificial insemination, and then implanting it into the uterus of the other partner. In that case the second partner would NOT be the child's biological mother. Let me put it a different way; in human sexual reproduction, the ovum carries a single X chromosome from the mother, and hence half of the child's genetic material comes from the mother's DNA. The sperm carries either an X or a Y chromosome from the father, and hence the other half of the child's genetic material comes from the father's DNA.

Now, then, what I want to know is if it is possible to take a donar sperm and remove the X or Y chromosome from the sperm that came from the man, and put in the X chromosome from the second woman in its place. Therefore you would have an ovum from one partner, carrying the X chromosome from that partner, and you would have a sperm carrying the X chromosome from the second partner. Now, if that sperm were used to fertilize the egg of the first partner, the resulting child would have 50% of its DNA from one woman, and the other 50% of its DNA from the second woman. So that child would quite literally have two BIOLOGICAL mothers, and hence the lesbian couple could quite literally have a child that is there's in every respect that any of us are the biological child of both our parents.

Now then, discuss. Is this possible, or simply not yet feasible?

I was watching an episode of the Atheist Experience the other day, and one of the hosts who identifies herself as a lesbian mother (her 'daughter' is biologically her partner's child through artificial insemination). It made me wonder whether or not it would be possible for medical science to allow artificial insemination in which, biologically, the resulting daughter would effectively have two biological mothers; or a mother and a female father if you prefer to think about it that way?

What I'm basically asking is if it is possible to take a donar sperm and remove its X or Y chromosome, similar to how we are able to remove the chromosome from an ovum, and then insert the X chromosome of one of the women, and then use that sperm to artificially inseminate the other woman? If that were possible it would seem to me to be an effective way for lesbian couples to have children.

Can anyone tell me whether medical science has advanced enough, or whether it is even possible to perform a procedure like this? And if it is possible, are there any significant hurdles that would need to be overcome? And if itsn't possible to modify the sperm in the way I'm suggesting, is there any other way that this could conceivably be done?

Does anyone know if there are any downsides to using UV spectrophotometry to determine the concentration of a purified protein? The only one I can really think of is that it would also measure any protein impurities the sample might contain in addition to the desired protein and add them into the final concentration it gives. Does anyone know if that is indeed a problem, and if there are any others?

Yes, but while only 20 Persians can actually engage the phalanx at a time, the reality is while that might be true, it's still the column of Persians would still be thousands of men deep. 20 Persians at the front, pushing against the phalanx, with thousands of Persians behind them who are pushing against these twenty. That being me back to my original question; how could the Greeks possibly have held their ground against such a massive amount of weight and momentum slamming into them like a battering ram? Again, the numbers just don't add up.

Another example, if the pass was only wide enough for one person to pass at a time, it's true that one person could conceivably hold back a much larger force in an actual sword fight, since only one enemy at a time could engage him. However, if 20 enemies did a hands-on-shoulders charge at him, each one right behind the one in front, then the single defender would not be able to offset that momentum and would fall beneath them.

So why didn't this happen in Thermopylae?

Could you ask your mother where she thinks this extra weight is coming from?

 

And, if I may be indelicate, is it possible your mother is a little on the heavy side and seeks to avoid personal responsibility for this situation.

To be honest, I suspect that she just isn't properly thinking about what she said; either that or we're thinking of two different situations. And no, she's not. At least no more so than most women in their 50s.

Okay, allow me to clarify exactly what I mean. When I say 'gain weight', I'm not talking about the the weight of fat that results from eating. It may well be possible for a person to eat 0.5 pounds of food and put on more than that in body fat, but that extra weight in fat would, unless the laws of physics have changed, by definition be at the expense of an equal amount of weight in something else in the body. In other words, lets say a scale says a person weighs exactly 180 lbs right before a meal. The person then consumes 3 lbs of food and drink and then goes back onto the scale. The scale would now read 183 lbs.

Now, what I'm trying to convince my mom is that it is not physically possible for that person, assuming that they don't eat or drink ANYTHING else that day, to weigh themselves the next morning and find that the scale says they now weigh, say, 185 lbs, or even still 183 lbs. Because as far as I can tell this is a closed system, and that extra 2 lbs of mass would by definition have to come from some external source, otherwise it would effectively be creating mass from nothing, which the laws of physics forbids.

Now, in this particular set of conditions, am I right or wrong?

I've been having this debate with my mom for ages now, and to be frank, she's really starting to annoy me, because her argument seems utterly vapid from a scientific point of view. I once made the common sense statement that it is not possible for a person to put on more weight than the net weight of their daily food consumption (in other words, if a person, ANY person, eats say 0.5 lbs of food in a single meal, the person can't gain more than 0.5 lbs as a direct result of only that 0.5 lbs of food consumed), and she keeps saying that I don't know what I'm talking about. To me this isn't even a topic worth debating, because it is a simple matter of conservation of mass, that extra weight would have to come from somewhere, it couldn't just come from nowhere.

Can someone please settle this debate once and for all, because it is getting very tiresome.

This is probably a question better suited to a history forum, but since it does largely involve basic physics, I thought I might as well just post it here. I recently watched a documentary on the famous Battle of Thermopylae, and I find myself at a loss to explain how the Spartans managed to hold their ground against a charge of thousands of Persians. In the pass there were 300 Spartans forming the phalanx blocking the Persian army from accessing the pass, and they were up against literally thousands of Persian soldiers. What I don't understand is this; as strong and well trained as the Spartans were, the fact remains that they were still only 300, backed by about 8000 other Greeks, who are somehow able to maintain their phalanx even though much larger number of Persians are smashing right into their front.

Now, to me the physics here seems pretty straight forward: tens of thousands of Persian infantry crashing head on to a phalanx of 300 Spartans. To me it should seem as if the Persians should have been able to smash right through the Greek lines like a battering ram through a curtain, since I don't care how strong the Spartans were, the mass and by extension the momentum of 10 000+ Persians would have dwarfed that of 300 Spartans. Yet despite this, when the 10 000 Persians first smashed into the phalanx, not only did it not move at all, but the Spartans were actually able to push them back and go on the offensive. The numbers just don't seem to add up here; 300 men withstanding the combined momentum of thousands? It doesn't seem possible.

Can someone tell me what I'm missing here? Because clearly something else must have been at work here, otherwise what I said would absolutely be correct.

I was watching Tom Cruise's 'War of the Worlds' the other day, which has more plot holes than a ton of Swiss cheese, but that aside, I want an opinion on the ending. In the movie and HG Wells' original story, the aliens are eventually wiped out by some Earth virus or bacteria. I used to think that this was entirely plausible since the extraterrestrials certainly wouldn't have encountered the germs before and thus would have no immunity against them, but now I'm not so sure. Setting aside the obvious absurdity of an advanced alien civilization being totally unprepared for foreign germs. While it is certainly true that the aliens would have no preexisting defence against alien (to them) microbes, I would think that it is very likely that our viruses and/or bacteria would likewise be entirely unadapted to the aliens.

So while the aliens would be unable to fight off the germs if they managed to infect the aliens, the germs (especially viruses) would likely be unable to infect the aliens. Can someone give me an opinion on which option is probably the most likely? It seems absurd to me that an Earth virus, which can only infect a small number of terrestrial life forms, would be able to infect and kill an alien life form which in all likelihood has completely different anatomy and cellular receptors.

Thoughts?

Can anyone explain to me why exactly it is that radioactive material decays at an exponential rate? To make my confusion more clear, take the following example. Let's say you have 1 gram of radioactive material, and for the pure sake of argument, though I admit that I'm just pulling this number out of a hat, let's assume that 10 trillion radioactive atoms are in this gram. The half-life of this fictional radioactive material is 1 million years.

Now before I go any further, I just want to make it clear that I more or less understand the mathematics behind radioactive decay (N=N0 x e^-kt), so I don't need an explanation of that, or of how to use said formula.

Now, even though I know how to use that formula to calculate the amount left after n amount of time, I have always been completely baffled by the idea of it decaying exponentially. In other words, if you were to ask someone on the street who knew absolutely nothing about radioactive decay: "If you start with 1 gram of radioactive material, and after 1 million years it will have decayed to 0.5 grams, how long will it take for it to completely disappear?" I can almost guarantee that their answer will be 2 million years (that's what common sense would dictate), and for the life of me I have never been able to figure out why this would not be the case, because it is completely counter intuitive. Can someone explain to me what the mechanism is that makes radioactive decay an exponential process, as opposed to one that occurs at a constant rate? Do we even know?

I'm just interested in knowing whether anyone thinks that the various stories in the Bible, and by that I mean those that are patently absurd as actually described in the Bible, could possibly have any grain of truth to them and actually be based (albeit extremely loosely) on actual events? For example, the story of Noah's Flood as described in the Bible has been so thoroughly debunked and is such an absurd claim that even most Christians and Jews don't even attempt to try and say that it's true. However, I remember reading somewhere that toward the end of the last ice age a massive ice dam in North America (at least I think it was in North America) broke, releasing a gargantuan amount of water into the world's oceans which caused ocean levels around the world to rise by over a hundred metres (I may have that number wrong, but either way, it rose by a huge amount).

I know that there are some scientists who believe that there may have been human civilizations existing in the last ice age (Atlantis being only the most obvious) on the basis that many artificial structures have been found under the ocean all around the world, some as far down as several dozen metres deep. Are there any non-bible literalists here who think that the story of Noah's Flood may be a reference to that event? It seems to me that it is possible at least in theory. Most myths and legends do tend to have at least a small grain of truth to them, however distorted.

A little while ago my uncle and I were discussing the theory of evolution and the appalling percentage of Americans (I'm Canadian, by the way) who still don't believe in evolution. I had made the claim that even though the theory may very well be incomplete, evolution is a proven phenomenon, which it is. And he made a point that I found interesting, and that was that the theory is indeed incomplete because we still are not able to explain how speciation occurs using the theory. The example he used was that even though humans have been breeding animals like dogs, cats, etc. for thousands of years, and artificially selecting for certain traits that we find appealing for one reason or another, which is effectively what evolution does naturally albeit at a hugely accelerated rate since we are able to specifically breed dog X with dog Y in order to get trait Z, which if left to natural evolution might take thousands or even millions of years to occur.

And that even though we have effectively been carrying out artificial evolution on animals at hugely accelerated rates for thousands of years, we have still been as yet unable to produce any actual new species by doing it. That is to say, for example, even though Chihuahuas and Great Danes look vastly different in every way due to our breeding, they are still technically the same species, because they could theoretically interbreed to produce fertile offspring (notwithstanding the fact that would probably be fatal if the Chihuahua was the female), and we have not yet succeeded in actually producing any new species of dog, as the definition of species stands.

That was just one example of what my uncle was trying to point out, he didn't just base his entire argument on that. He concluded that while the Theory of Evolution is indeed accurate, and I know for a fact that it is, it currently fails to adequately explain how speciation occurs. And I must say, I did find his argument compelling. Can anyone explain if it has any flaws, and if so, what they are?

And just to be perfectly clear, I am trying to better my understanding of Evolution, not pick holes in the theory.

No, I'm talking about dust accumulating on the surface of the moon that comes from space. Space isn't a perfect vacuum, and as was said before, the moon lack any sort of atmosphere, therefore any interstellar dust that drifts to the surface of the moon from space should theoretically stay there. Why isn't this the case?

Before I go any farther, I just want to make it clear that I am NOT a creationist, I NEVER have been a creationist, and I NEVER will be a creationist. I despise creationism. I know and believe that the Earth is ~4.2 billion years old.

Okay, to my point. I was watching an episode of the Atheist Experience the other day, and some moronic creationist caller started saying that he believes that the fact that the moon has so little dust on its surface 'proves' that the Earth is less than 10 000 years old. Obviously this is complete nonsense, but I confess that I was slightly taken aback, because it seems like a fairly valid argument when taken at face value. Can someone explain why there ISN'T considerably more dust on the lunar surface than there is? I mean, it should have been accumulating for billions of years, after all. Even if it were at a rate of less than a nanometre/decade, there should have still been at least a few feet of it, not the 3/4 inches that there actually is.

Again, I have absolutely no doubt of the age of the Earth. This is simply something that I found interesting.