Sisyphus

The point I was trying to make is that medicine is (or is not) part of physics in the same way that science as a whole is or is not part of philosophy, depending on how you look at it. The physicist and the doctor deal with different questions, but they're different just because the physicist's are more fundamental - the doctor relies on physics and deals with a specialized physical situation (albeit one with a great deal of specialized knowledge, and its own many conventions and methods) even if he doesn't think of it that way on a daily basis. In the same way, the philosopher deals with different questions than the scientist, not because they're separate, but because one is more fundamental.

That's an amusingly literal solution, but I have to disagree with you. "Lifting" is always just separating two massive bodies (insert wonderbra jokes). No matter what two objects you're talking about, each exerts exactly the same gravity on the other. When you stand on the Earth and lift a rock, you're not just moving the rock, you're moving the Earth, too. You are, in fact, exerting the same force on both, but since the Earth is so much bigger than the rock, it moves a much smaller amount, inversely proportional to its size. When you drop it, the rock accelerates towards the Earth, and the Earth accelerates towards the rock.

But since when is there an objective metric of fairness? You say paying the same amount is fair, but most people disagree with you. "Giving the same" is all well and good, but the same what? The same quantity? The same percentage? The same imposition? Or going even further, is not any tax code implemented in a democracy fair by definition? We voted on it! Alternatively, as DH says, there are those who say that any taxation is objectively, inherently unfair. Furthermore, in reality "fairness," however you're going to define it, is still only one of several factors weighing against one another. Simple possibility has to be considered. You can't just charge a universal "citizenship fee," because it would have to be more than a lot of people have all together. Even if it could be managed, pragmatically it's still a stupid idea. Taxing most of the money from the poor would just make them extremely poor, and crash the economy. You'd end up with feudalism. So right off the bat, "what's best for the economy" (however THAT is defined) is a serious factor to weigh against "what is most fair." And all that is still assuming a constant target revenue! Should it be? How bad are deficits? What about surpluses? Not to mention political considerations. You could have a perfect theoretical balance of everything else, but it's worthless if you can't get it through Congress...

If physics is about deciding how the physical body works, then it can be part of medicine! I don't how long this analogy will hold up, but it's doing fine so far.

Part of the trouble is that "philosophy" is an extremely broad term, and includes a number of subjects that really (I think) would be better off considered separately, since calling it all "philosophy" can lead to confusion, especially among "scientifically-minded" people. So yeah, there's a lot of "fluffiness" that rightly or wrongly calls itself philosophy, but that's not all there is. Really, though, it is very much inseparable. Basically, philosophy just deals with fundamental questions. It's not so much "why questions," as certain people like to say, but more "what questions." What is existence, what is rationality, what is necessary, what is contradiction, etc. Science is a tool, grounded in a great many philosophical assumptions, for coaxing empirical data out of existence. It is philosophy which provides and then continually reevaluates those assumptions, and "analyzes" the data. It's a difficult process to really explain without going very, very deeply into it, but science is highly dependent on epistemology, ontology, logic, and various inquiries of metaphysics, and historically the greatest scientific shifts have been rooted in philosophical hypotheses, and in broadening "scientific" inquiry into what previously had been considered mere fluffy old philosophy. Now, that's not to say that scientists need to study philosophy in order to do their jobs. They can (and usually do) only have a grasp of certain concepts, without even necessarily being aware how much more there is to it. Analogously, medical doctors don't need to know about advanced physics to cure patients and do effective research, even though their subjects (human bodies) are ultimately physical objects being physically manipulated.

I think the idea is that the photon won't fall at all because its mass is zero, and hence so is the gravitational force, and so is the acceleration. That's why it's not analogous to a rifle bullet, and why you won't see elliptical orbits like you would with Newtonian equations. It will go in a straight line - through space. The reason it nevertheless does (in a sense) curve is that space itself is not "straight." One of the crazy aspects of GR is that straight lines don't behave like we intuitively expect them to, and don't appear straight from other perspectives. That's how you can get things like black holes, where space is "bent" so much that no straight line is ever going to lead you anywhere but elsewhere inside the black hole. What you're looking for, then, is I guess what the photon's path would look like from Earth. And no, it wouldn't be straight. I'm not going to do the math myself, though, because a)I'm lazy and b)I'm afraid I might embarrass myself.

Metaphysics is a legitimate branch of philosophy, and not comparable to the hocus pocus stuff. It's a term that gets misused a lot, but hey, so does "science."

It will never get that high. In fact, it's already declining in places where sex education is common and contraceptives are widely available. For example, infection rates in the United States peaked in 1996. I would also disagree that it has anything to do with "sexual ethics," or that they're eroding with time. If anything, irresponsible sex is less socially acceptable than it's ever been. But I guess we probably have different ideas of what good "sexual ethics" are.

I was considering a couple of different jokes here, one defending them both by bringing in causality in relativity, the other claiming that they're both wrong and that the Anbar Awakening is actually one of my successes, it being a direct result of a comment I made last week. Instead, I'm just going to comment that it's interesting that they both think it's something worth taking credit for, when to me it doesn't seem that clear cut at all. Is a better armed, better organized, and more widespread non-governmental sectarian militia necessarily a step in the right direction? The Iraqi government, at least, doesn't seem to think so: http://afp.google.com/article/ALeqM5iMzKGlyT_ahqRjtyXrAUrKIQLncA

Helium. He's been inhaling it straight for extended periods, and his brain is deprived of oxygen.

On the contrary, there most certainly is. Everything has some elasticity, and steel actually has quite a bit compared with, say, ceramics or crystals.

I'm guessing Mr. Skeptic means that with something like social security, you "get your money back" when you collect. So in a way, the real "cost" of social security is not the sum of social security taxes, but sum taxes minus sum payments. It's still not "free," and you won't necessarily individually get "a return on your investment," but it's still far less expensive than a first glance would indicate. This, I guess, would contrast with military spending, since they're never going to give me a tank when they're done with it.

Fair enough. I'll concede I hadn't thought of rolling resistance, but to be fair, that's not the same thing as friction. It's the energy used up in the continuous deformation of the wheel and/or surface. The surface friction is just in the axles.

No, it doesn't do those things. That company promises it will. Well, it's different because private aircraft are extremely rare, take off and land at airports, are closely monitored by (already stretched) air traffic controllers, and are flown by pilots with rigorous training, including many, many hours of one on one instruction from certified instructors. The idea of a "flying car" that can do anything like take the place of ground cars obviously implies enormous differences from that. I'm not trying to be a downer. I'm a technological optimist (and a sci fi fan) and I know that technology and society can change in unexpected ways in relatively short amounts of time, so I'm not saying it's "impossible," just "currently unforeseeable." Remember, the first "flying cars" were marketed in 1937! Where are they?

Do you know something about flying cars that I don't? Because as far as I am aware, they don't exist, and therefore are totally pollution free! Seriously, though, you can't make a blanket statement about all potential technologies like that. I say we cross that bridge (or hover across the river) when we come to it. As for fundamental issues of replacing things whizzing along the ground with things whizzing through the sky, I can't say I agree that the overall "footprint" would increase. Quite the opposite, actually. How much of the landscape is currently covered by paved roadways? Are more birds likely to be killed by flying cars than animals are currently killed by ground cars? How much pollution (and wasted time) is the result of sitting in traffic and circuitous routes? That said, this is almost certainly a moot discussion. Flying cars aren't coming. We've been promised by popular culture that they're right around the corner for the better part of a century, and I'm done waiting. Plus, I can't help but think the problems are too great to be solved in the foreseeable future, anyway. Millions of poorly trained "pilots" sharing a tightly confined airspace? At best you couldn't have people controlling their own "cars" - everything would have to be automated and coordinated across entire regions. It's much more complex than ground transport, and failures are much more catastrophic: a fender bender with ground cars becomes a plane coming down on my roof with flying cars.

I have credit cards as an emergency backup (though I've never had to use them that way), and as an easy way to build credit rating, so that I can get a good, safe loan if I ever need one. I just pay for pretty much everything with a credit card, then immediately pay it off. I've been doing it for years, and have yet to be charged a single cent of interest.

I haven't seen it, but based only on this thread, it sounds like their worthwhile arguments aren't against the science, just the efficacy of some of the things we're doing about it, e.g. "carbon trading." The rest just sounds like junk science and name-calling of well-meaning people. And even if they didn't frame it in that way, the description sounds like they're implicitly supporting politics that would "create a healthier ecosystem."

Indeed. Surface friction will, of course, affect the heavier rider more, but surface friction in this case is just in the axles, which all experience and common sense say will be far less of a factor than air resistance, which in any likely scenario (i.e., we're assuming they're both physically normal humans and neither one is dragging a parachute, etc.) will clearly favor the heavier rider.

Is a resident of Earth really asking this?

I don't understand what's going on here. Is absolute1 saying he blew up the Earth with his mind, or just that he could? If the former, does that mean this is the afterlife? And if it's the latter, shouldn't we try to stop him?

Maybe you should elaborate on the question a little?

What?

Theoretically, it would eventually reach that point. But that would take 50 billion years, at which point the Earth and the Moon will long since have been destroyed by the death of the Sun.

I agree!

The "religion card" is just ignored here. This policy was arrived at by long and painful experience.