QUOTE(NorthSideSox72 @ Aug 16, 2006 -> 01:12 PM)
These are two interesting parallels, but I need to point out a couple things. One, DDT didn't kill off as many things as it could have because we stopped using it. And cell phones don't cause cancer (directly, at least - they may still be a contributor) because their radiation levels are too low. What is common about these two things is that scientific knowledge, in both cases, influenced policy and action is such a way as to prevent further disaster. DDT stopped being used, and cell phone companies have been very wary of radiation levels from their units.
Just an interesting thing.
He does have a point on some level...and that's one of the things that makes science actually worth doing, is that sometimes not everyone is going to agree on some theory, and therefore, it can be tough to make decisions based on some theories. And it can be even tougher to judge when one side of an issue has won the day, especially if you are not well versed on a topic. Especially if there is some well-funded political organization dedicated to convincing people that the other side is correct regardless of the science.
But let's deal with the specific cases he cites, Global Warming and Evolution. First and foremost, let me say this in response to this claim:
Yes, it is true the earth has been very hot and very cold many times in the past. And almost regardless of what we put into the atmosphere, the Earth, and Life itself on Earth, and mankind, are going to survive. But there's one thing you're missing that is of some importance...humankind has not always been on earth. Humankind has not always set down roots in places, and developed societies based around the climate in certain areas. This is the new feature, and it's the real concern in global warming. Should you be concerned that we're going to turn the earth into Venus? Pretty darn doubtful. Should you be concerned that maybe the water resources that feed a city of 10 million might alter their paths, or dry up because of this phenomenon? Or that currently arable land will dry up, causing food shortages in some regions? Absolutely. Just because the Earth will survive doesn't mean that the costs of doing nothing won't be judged to be a disaster by many people.
But now, on to the big picture. Here we see, overall, in terms of both global warming and evolution, the classic argument that we are always ignorant, that no matter how much we learn, we can never know anything. No matter how many lines of evidence we have that organisms evolve by natural selection, or that increasing CO2 in the atmosphere can change the climate, we can never know enough. This argument is a bit of an odd one, because it is applied so unfairly. It is only really applied when people have some other reason to doubt every bit of the science on a topic with which they disagree. We only have a few thousand years of evidence for how gravity works, so why should we conclude that Isaac Newton's law is an accurate represntation? We have only a few decades of evidence for the quantum behavior of the electron, so why should we conclude that computers work?
Here is the big picture...if you want to actually learn about something, then learn about it. Don't tell us that we can't learn about something or that we're guaranteed to be wrong unless you actually know enough about something and care enough to learn the details. The theory of evolution is not just based on "Some bones". The theory of evolution by natural selection is based on a century worth of data collected in the field and in laboratories that tells literally hundreds of thousands of different stories, from the formation of the different kingdoms of life to the evolution of specific lineages, to the decline and extinction of those lineages, and so on, all the way up to the present. You can go into the laboratory and see evolution happening. Hell, by dumping tons of antibiotics on the world, we're doing our own natural selection experiments. You can trace the evolution of genes back through time to the species where they first appeared. You can trace species from the era they appeared, through their rise, and through their fall. Do we have every single answer? No. But we have a lot more than just "Some bones". We have a fully funtioning theory that is testable, makes predictions, and simply has not been falsified no matter where anyone has looked.
Global warming is roughly the same way. Yes, a half a century ago, our understanding of the connections in the system were not as good as they are now. But that doesn't mean we don't have it right now. Now what we have is a working model which makes predictions which come true. Based on physics, we can understand that CO2 absorbs energy in a specific light wavelength, and as you increase the CO2 content of the atmosphere, you absorb more energy, forcing the planet to increase its temperature in order to radiate at a different frequency. We can tell from geology that in the past, both millions of years ago and thousands of years ago, large temperature spikes have been concurrent with large increases in atmospheric CO2. We can tell from chemistry that the CO2 content has gone up, not just from measuring the CO2 in the atmosphere but by looking at a huge number of other proxies, like the acidity of the ocean and so forth. We can tell from satellites that the oceans themselves are expanding as sea level rises, and this would be predicted if the oceans were warming (thermal expansion). And using computers to take into account more variables than we can in our heads, we can even estimate how important the different forcings are, and what their results are.
So, you are right in 1 sense...an answer derived through science cannot just be taken as concrete. But that is in fact the beauty of science, not its flaw. If you want to overturn something in science, you need evidence. And you need evidence equal to what you're trying to overthrow. In terms of evolution, there simply isn't any. It tells a story. It's not the story of every single cell ever to exist on this planet, but it is a shockingly complete story. Unbelievably complete. Vastly more than just "some bones". In terms of anthropogenic global warming, the evidence that says it isn't happening is almost non-existent at this point, the only debate is to the intensity of it and the results. So you ask why scientists claim these are unquestionable facts? Well, the answer to that is simple...scientists have learned enough to make that judgement on their own, and are telling you that from their position.
If you want to say that none of it is happening and say that someone should not say that evolution by natural selection or anthropogenic global warming is not true, then actually learn what case is being made, take a look at the evidence, and judge for yourself. But if you're willing to throw the evidence for either of those out the window as flimsy, having spent a significant amount of time learning about both of them, I will say from my position that I believe you are completely wrong if you want to question either of those theories. And if I had the time and didn't have to keep entering data into this PC at some point, I could spend hours giving you well-researched, tested facts that would show why.
But all I will ask is this...don't just make the argument that we are forever ignorant without giving me a reason to believe that we are ignorant in this case. Has science said things incorrectly in the past? Of course. Will it in the future? Of course. But you can not simply say that "Science has made mistakes on issue x or issue y in the past, so we should never trust scientists on issue z" without either giving me a reason to suspect that we are wrong on issue z. That is not a logical progression, and it is a mistake to pretend it is so.
It is for that same reason that some will take folks who say that the evidence for evolution by natural selection or anthropogenic global warming and say that they should stop using their computers because they can't guarantee that the electricity will keep working the way it always has, because that sort of argument that we are always ignorant can and should be applied in any and every aspect of science. You just have more experience with certain accomplishments of science, so you have a habit of not applying it to those theories with which you actually have familiarity. You don't, for example, put furniture on your ceiling just in case gravity stops working, because you have extensive experience with gravity, so you don't think to say "Well science says gravity works this way, but science has been wrong before, so I should be careful." However, that is another expression of the exact same logic which you are trying to apply. But with Gravity, you know enough not to doubt how it works, because you have expereinced it yourself and you know the evidence.