If we are only allowed to have opinions about that which we are experts, then very few opinions will be had.  Unfortunately, I do no have a PhD in Decision Sciences, or I would opine further on the matter.

So from what you're saying if I don't have a phd in a subject than I cannot have an opinion about it.  So essentially, according to your philosophy, I cannot have an opinion about anything, since I don't have a phd, or any other degree.  All the reading I do, and research means nothing unless I have gone to the top level?  That's rather ridiculous.

I can give my opinions to other people until I'm blue in the face.  It doesn't mean I'm right about it.  It doesn't mean you have to listen to it.  I don't know too many people here who start off every post with 'Well, since I'm an expert in X...'  I know I certainly don't.  

As an aside, just because a person has a degree it doesn't mean they are smart. It just means they took and passed the required course work. 

I like how some people have superpowers to detect a massive government conspiracy that nobody else has been able to figure out, without ever having to leave their mom's basement.  Two great examples are the "moon landing hoax" and the "9/11 conspiracy".  Now I read a lot but to go out and claim, "Planes just don't crash like that" or "If it was really a plane then something different would have happened." Those at the FAA who spend their careers studying plane crashes are apparently dupes, like those biologists who can't figure out a planet is really 6,000 years old or those engineers at NASA who can't build a spacecraft to travel in outerspace.

On the other hand there are those who are quite pleased to be proven wrong.  I'll watch Mythbusters and be outstanded that one of my commonly held beliefs is proven wrong.  I just told my friend today that leaving the tail end of a pickup up is actually more fuel efficient and she was glad for having been proven wrong.  However there are those who hold onto their errors like a religion.  Study after study shows human's impact on global warming so they'll skim science articles from 1970 that have already been discounted and announce that we are all buying into a huge hoax.  Kinda like how creationists will take an old study about space dust that has been refuted and use it to point out that the planet can't be billions of years old.

A dishonest person is one who is always right. 

The moon landing hoax stuff actually has decent evidence. There was even a very out spoken japanese guy (he was pretty important in the japanese scientific community) who spoke out against the U.S. actually landing on the moon during and after the moon landings (for several reasons all ranging from it not being possible due to the technology the U.S. had at the time to the film being fake).

There's actually some good evidence against the moon landing and it's all in everything that has been given to us by the government. However, there is also good evidence for the moon landing.  It's also rather strange that we haven't gone back to the moon and are planning to in some 7 years.

Anyway, I guess what I was trying to say is that all conspiracy theories are not made equally. Not that I believe any of them. 

I disagree. An eductated person can look at the research and evidence for themselves and form an opinon based on the conclusions reached by the experts. I agree that a nonexpert is unlikley to add anything new to the debate but they can still asses the conlusion and make an informed opinion. The decision on say whether global warming is happening can be based on factors such as the reliability of the report in question. If we can see that funding comes form the energy inducstry then we can legitimatly suspect bias. If the research is from an unknown institute and is peer reviewed in only the lowest teir of scientific journals then again we can take it with a pinch of salt. But if the report is from a respected expert or team of experts, working for a respected academic institue and has published an peer reviewed in the correct journals then we can make an informed decision to take it seriously. We do not need to understand the precise technicalities only the conlcusions and perhaps more importantly who came to those conclusions.

I think its fairly well established  that black holes do exist.

String theory certainly exists but whether its an acurate description of reality is contentious to say the least. I base this on the fact that a google search will reveal a number of articles from respected scientists that say exactly this. Namely that string theory, whilst promising, is in no way proven. It still has many holes in it. I do not need to understand the horrendous maths required to reach theses conclusions I just need to understand that the scientific community has reached these conclusions.

What if one good searches stuff to study? 

I would question whether these people are actually intelligent if they say this. 

Indeed. 

Indeed. I would agree that a meta study of all the conclusions of all the studies would suggets quite strongly that human activity is responsible for global warming. 

I tend to agree that we should trust the consensus reached by science. It tends to be right more often than not. But it does not hurt to look at the apparent holes in the theories.

If you were meaning that theists say, "I think God did it" - I'd have to say you run with a more enlightened crowd of theists than I do.

The theists that I have experience with say things like "I know God did X" or "I know God spoke to me". When you ask how they know, they respond with "He said he did" or "I just know" or "That's where faith comes in" or "I experienced God in X".  

Oh for Jakes sake, please take the chip off your shoulder.  Move on.

If I'm not an expert in the field of 'X', how is it I have the right to vote on an initiative regarding 'X'?

You may substitute "stem-cell research" or "a woman's right to choose" or "the right to die" or "putting a new bridge over the Missouri River" or "who should be the next president" for 'X'.

Also, think about medical decisions.  When it comes down to brass tacks, YOU make the decision whether or not to pursue a specific treatment, not the doctor.  Yes, the doctor has studied medicine,  has much more knowledge than you and can counsel you, but the final decision is yours. 

After the past month I'm about ready to become my own doctor because in at least two cases, I did know more than the doctor...and that's scary.  

These guys get paid big bucks for what, exactly? 

Maybe it's a local phenomenon, but I've watched two health care professionals misdiagnose me this month.  The one today showed terrible critical thinking skills and when I pointed it out she wasn't exactly thrilled with me.

wow! How cunning of you......

I think it's a bit cranky to demand that people stop having opinions about things they're not experts on. It's not the opinions that are the problem, but the method of forming them.

I'm not an expert on evolution. My degrees are not even remotely related. But, I've read Darwin, Dawkins, and my college biology text. I've held fossils in my hand. I've watched bacteria evolve with my own eye. I am qualified to hold the opinion that evolution is fact. I can talk a little bit about the mechanisms of selection, and if I reviewed for a bit, I could probably even hold my own on the processes by which mutations are passed on genetically.

I hold no PhD in logic, yet I am quite competent because I have studied it independently, and a little in college. I have been reading sociology dissertations for years, and am well versed in psychology, even though it was not even my minor in college.

Am I an expert? No. But, I am perfectly qualified to write something, cite my source, and draw my own logical conclusions based on what I know.

Following the dictates of logic, I am also forced to acknowledge when I don't have enough data to form an opinion. In these cases, I normally defer to the leading authorities who do have PhDs. This knowledge is usually enough to make my opinion valid, no?

Clearly there is something to be said about this. Clearly you can not necessarily be an expert by Google/ Wikipedia searching. But what about reading books and studies on the subjects? But even then books and studies aren't always reliable. Even PhDs can be given to Creationists at Christian Universities. Even at main stream Universities Theology is counted as if it were a real discipline.

I don't claim to be an expert in the sciences, but I do have a good enough grasp on the theory of evolution by natural selection to have a certain amount of expertise in explaining it to less educated people.

After a debate in the pub the other night my friend (a philosophy student at Bristol) was complaining that some of the others weren't philosophically trained. Sure enough their arguments were less rounded and less sound than those of him and myself but that does not rule out the value of their arguments, nor the intelligence of those other participants. At the same time one friend at the pub who is a biology student was just as able as us to argue and debate philosophically.

All you need necessarily to be an expert is knowledge, both of the facts and how to acquire the facts reliably. I generally acquire my knowledge through reading, and sometimes through my education. Occasionally I may check something like a date up on Wikipedia (on the basis of what reason would anyone have to lie about the year a certain person was born or a certain book was published.

Of course there are different levels of expertise, and the highest level of expertise (in the academic activities) are those who spend their lives studying it at an academic level just as those who have expertise in plumbing are plumbers.

I'm not denying it's useful but it's also very dangerous, any idiot can put stuff up there, and it won't be sifted through for months.

I actually just said that for kicks.

But I have experienced it >_>