Evolver said:
Believe me, I have not become personally offended in the least. I was only vehemently defending philosophy, which I believe is a crucial ingredient when it comes to theoretical thinking. Equally important are an understanding of physics as well as a backbone of mathematics. If you would have expressed a dislike for either of those I would have just as readily defended their importance. Though this is getting slightly off topic, believe me when I say there are no personal issues here, I am only interested in the exchange of ideas, and I would like nothing more than for that to continue.
As for philosophers, they receive flak for attempting to force definitions of concepts. They ardently push for defining things, because definition equals clarity. If anything, they should be thanked for that contribution as the inverse to attempting to force definition, is that assumptions get made. And when scientific "fact" becomes based on assumption... then there is a serious problem. I'm not sure what philosophers you are speaking of that attempt to convolute people's thoughts, but that sounds more like a personal problem with that individual "philosopher" as opposed to a problem with philosophy in general.
Because philosophers push for definition and clarity, they attempt to define things that very often are hard to define, so it becomes labeled as metaphysical. Before Einstein had enough pieces of the puzzle for his theories of relativity, they could have been thought of as metaphysical concepts. Here is a dictionary definition of metaphysical:
"a. concerned with abstract thought or subjects, as existence, causality, or truth.
b. concerned with first principles and ultimate grounds, as being, time, or substance."
According to these definitions... Einstein's theories are STILL considered metaphysical.
Any philosopher worth their weight in gold would NEVER attempt to make a concept more complex. If they did, then by definition, they wouldn't even be a real philosopher.
And you're right, I feel in order to continue in conversations there has to be a universal understanding of words involved. That's why physics uses equations with symbols that represent a concept.. there is no debate to that symbols meaning then. In our case, I was trying to establish those definitions by attempting to define "reality" and existence". And you're right, maybe most people wouldn't agree with my definition of reality... but reality is subjective, and when you are trying to compare it with something that is objective (like how i defined existence) then new definitions are required.
Wikipedia makes an attempt to be unbiased and to reflect common knowledge about particular subjects. The following is the beginning of the entry on reality there:
Reality, in everyday usage, means "the state of things as they actually exist." In a sense it is what is real.[1] The term reality, in its widest sense, includes everything that is, whether or not it is observable or comprehensible. Reality in this sense includes being and sometimes is considered to include nothingness, where existence is often restricted to being (compare with nature).
The term 'reality' First appeared in the English language in 1550, originally a legal term in the sense of "fixed property." It originated from the Modern Latin term 'realitatem' which was from Late Latin 'realis'; The meaning such as "real existence" is from 1647 onwards." [2]
If you go and see what different philosophical schools of thought have to say about reality, you will find many different definitions. The definition above entails an external reality separate from our perception. Of course positivists and to an extreme solipsists would question that. But when it comes to day-to-day life, I think the definition above is what most people have in mind, and it conveys a meaning clear enough for people to communicate. The exact wording of the definition above could be disputed, but you can see that it does not make a big distinction between "reality" and "existence".
I think most people would consider as "reality", the set of objects and events that "are out there" or, in other words, "exist". Of course this implies that you believe that these things actually exist independent from your perception, but most people do have that belief. Now, let's assume for a moment that I deny the existence of things which I don't or can't perceive (let's ignore the difference for this argument). I could still use the word "reality" with the same meaning than those who do believe in a separate existence assign to it. The reason I can do that is because I can picture in my mind what they think. So, using the word with the same meaning I could say that I don't believe in "reality", and even we have opposite views, we can still communicate and understand what the differences are because we both agree on the meaning of the word "reality".
The same could be said of other words. I may say "I don't believe in God". When I say God, I am referring to the concept that most people have in mind when they say it. Someone may always want to split hairs and say that different religions have a different concept of God. But when I say God, I am referring to a generalization of all these ideas, (giving more preponderance to the most common).
Some may even say that my concept of God is wrong, that they have the right definition. But there is no right or wrong definition of God. God is just three letters and it can be used for any purpose you like. It is just that we try to use it in a consistent way so that we can communicate with each other and have some certainty that when someone says the word, the picture they have in their mind is what we think. If we use the most common definition, then there is better chance of not having misunderstandings.
Back to "reality", I think its usage in physics refers to the world out there (as opposite to our imagination, dreams, hallucinations, etc). Of course we should say that if we believe that mental processes are the result of brain activity, then imagination, dreams and hallucinations are also real as processes. But what we don't consider real is their content, what they represent. Someone could also dispute this. Everything can be argued, and you can have an unending discussion. But if we try to ignore some of the differences (as long as they don't pop up as a big stumbling block) and look for some common ground, that may be more beneficial.
When I initiated this thread, I had in mind initiating a debate about the validity of the concept of reality at the macroscopic level, specially considering that amplification (measurement) of a quantum event can produce paradoxical results. I did not have in mind getting into a discussion of what "reality" means, because I thought there was enough consensus on it's meaning.
In other posts I have tried to steer the discussion more in that direction. When we think about reality, we think of certain objects out there which have a more or less deffinite position, orientation, and other attributes. These attributes may change, but they have a more or less deffinite value at each moment in time. If, on the other hand, someone told us that a Schodringer cat can be "realy" in a superposition of live/dead then that would be a challenge to the concept of realism the way we normally understand it. This challenge could mean that simply we can't assume that all things can be classified as real or not real, or it could on the other hand mean that we need to modify our definition of reality to include "other realities" such as in the Many Worlds Interpretation of Quantum Mechanics.
At the microscopic level, this debate has been going on for a long time, having probably started with the famous discussions between Eintein and Bohr. But at the macroscopic level there is not much discussion. I think this is due to the fact that once a measurement is made, the state of the system is assumed to jump to one of the eigenvalues of the observable being measured, and classical reality is thought to emerge (Nowadays this process being described in terms of environment-induced decoherence).
Before you make a measurement of a quantum system you have a superposition of states, and the ordinary concept of reality is in conflict with that stage of the process. But once you made the measurement, you get a definite value for the observable. If you don't know what that value is, you can still describe the situation with a diagonal density matrix which represents a "mixture" of states as opposed to a "pure state". In the mixture, you assume that the system is "realy" in one of the eigenstates. So, after that point, there is (apparently) not problem with the concept of independent reality. Except for a few very peculiar cases, the transition from quantum to classical behavior happens when a microscopic (typicaly subatomic) quantum system interacts with a macroscopic one.