Defining Physicalness: Inviting Physicalists to Weigh In

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In summary, physicalism is the belief that every observable process is completely determined by physical laws.
  • #1
Les Sleeth
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Debates about physicalism are sometimes hampered because participants can't seem to agree what "physical" is. I'd like to invite all physicalists and those who believe they are clear about what physicalness is to create an exact definition.

I'll offer my opinion first. I think physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass. Since all mass we know of is believed to have originated with the Big Bang, then I'd also restrict the definition of physical to how mass and mass effects have developed from that event.

In a past thread I posted the following in support of my definition:

Princeton's Word Reference site give the definition of physical science here:

- the science of matter and energy and their interactions


On the same page you can find a definition for physicalness:

- the quality of being physical; consisting of matter


The Word Reference site gives several relevant definitions of physical here:


1* physical - involving the body as distinguished from the mind or spirit . . .
2* physical - relating to the sciences dealing with matter and energy; especially physics; "physical sciences"; "physical laws"
3* physical, tangible, touchable - having substance or material existence; perceptible to the senses; "a physical manifestation"; "surrounded by tangible objects"
4* physical - according with material things or natural laws (other than those peculiar to living matter); "a reflex response to physical stimuli"
6* physical - concerned with material things; "physical properties"; "the physical characteristics of the earth"; "the physical size of a computer"


Of Physicalism the Wikipedia says:

Physicalism is the metaphysical position that everything is physical; that is, that there are no kinds of things other than physical things. Likewise, physicalism about the mental is a position in philosophy of mind which holds that the mind is a physical thing in some sense. This position is also called "materialism", but the term "physicalism" is preferable because it does not have any misleading connotations, and because it carries an emphasis on the physical, meaning whatever is described ultimately by physics -- that is, matter and energy.
 
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  • #2
I would define physical laws as those laws that can be framed in the language of mathematics. Or less strictly, the language of logic. For example, if we find a theory of consciousness that quantitatively relates experiences to information processors, as Chalmer's suggests, I would call this a physical theory of consciousness. This raises the question of whether the universe is mathematical or merely approximated by math. If it's the former, then physicalism completely describes the universe, with the possible exception of its creation. If its the latter, physicalism, at least as we know it today, will fall short.
 
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  • #3
StatusX said:
I would define physical laws as those laws that can be framed in the language of mathematics. Or less strictly, the language of logic. For example, if we find a theory of consciousness that quantitatively relates experiences to information processors, as Chalmer's suggests, I would call this a physical theory of consciousness. This raises the question of whether the universe is mathematical or merely approximated by math. If it's the former, then physicalism completely describes the universe, with the possible exception of its creation. If its the latter, physicalism, at least as we know it today, will fall short.

You might be correct, but I haven't asked for what physical "laws" are. That is entirely different! Once you reduce physicalness to the abstraction of laws and logic and math, you've put the ball squarely in your own (physicalist) court. Physical might follow laws, and be predicted by math, but that isn't what it is.

Please stick to a definition of physicalness itself. What is it?
 
  • #4
Ok, then I would define physicalism as the position that every observable process is completely determined by physical laws, as described above. To put this another way, if two systems are identical in every physical way, they cannot be different in any other way. By "physical way" I mean whatever parameters go into the final mathematical theory (eg, matter, space, qualia). As for unobservable processes, I would say that physicalists deny such a thing could exist.
 
  • #5
StatusX said:
Ok, then I would define physicalism as the position that every observable process is completely determined by physical laws, as described above. To put this another way, if two systems are identical in every physical way, they cannot be different in any other way. By "physical way" I mean whatever parameters go into the final mathematical theory (eg, matter, space, qualia). As for unobservable processes, I would say that physicalists deny such a thing could exist.

I'm sorry if I've confused the issue. I didn't ask for a definition of physicalism. I am asking what "physical" means. What are the properties of physicalness? How can you tell if you are looking at something physical (without any reference to laws or calculation)? What qualities, if observed, would make an objective thinker say, " that is physical"? What qualities, if observed, would make an objective thinker say, "that's not physical"? You can't cite obeying "laws" because those are determined after the fact of consistantly observing the same qualities. I am asking for what can be observed in the raw, one time, that makes something physical.
 
  • #6
I'm sorry. The reason for the confusion is probably that (and to answer your question as best I can) as a physicalist, I believe everything is physical, and the question doesn't really make sense to me. And I don't see how you can say anything about the world without some basic rules. Don't forget, the mass and energy in your own defintion are not intrinsic qualities, but only arise from the rules we have discovered to describe functional relationships.
 
  • #7
StatusX said:
I'm sorry. The reason for the confusion is probably that (and to answer your question as best I can) as a physicalist, I believe everything is physical, and the question doesn't really make sense to me. And I don't see how you can say anything about the world without some basic rules. Don't forget, the mass and energy in your own defintion are not intrinsic qualities, but only arise from the rules we have discovered to describe functional relationships.

You are admitting to a lack of objectivity. How can anyone trust such an opinion? What if someone comes along and picks out of reality only that which gives support to their spiritual beliefs, and ignores anything which doesn't?

For a minute, can't you just look at reality without your filters and concepts in place and describe what you see that is physical? We can argue later what is birthed by physicalness and what isn't.

Let's just define the OBSERVABLE properties (for now) which most define physicalness for what it is.
 
  • #8
Anything that we can observe must have at least intitiated a physical process since our senses are physical. Assume we observe something "non-physical" and we can trace the physical processes back somehow from where they interacted with our senses to point where the laws of physics are violated (as they must be since otherwise the phenomenon would be physical). Now I can't think of anything like this, but if it exists, I would say that all it means is our laws are incomplete, and as long as the additional laws followed some kind of basic logic, preferably framable with math, a physicalist view can be sustained. If they can't, well have to rethink a lot of things, but I'm sure many scientists would first die trying.

One other possibility that comes to mind is that a phenomenon can strictly follow the laws of physics, specifically quantum mechanics, but the chances of it happening the way it did are so astronomically small that pure luck can be ruled out. (eg, a ten foot tall gold crucifix spontaneously forms from atoms in the air) Again, I'm sure many, many alternative theories will be proposed by scientists first, and maybe they'll find one that works.

So, for my fourth try, I'll say that phenomena are non-physical if they cannot be explained using logic or math or if they can be, but something so unlikely has happened that some unseen force must be responsible. If this isn't what you wanted, I think I'm going to have to give up.
 
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  • #9
Les Sleeth said:
You might be correct, but I haven't asked for what physical "laws" are. That is entirely different! Once you reduce physicalness to the abstraction of laws and logic and math, you've put the ball squarely in your own (physicalist) court. Physical might follow laws, and be predicted by math, but that isn't what it is.

Please stick to a definition of physicalness itself. What is it?

Given his framework, the definition of physical would be "anything that obeys mathematical laws." This would be about the same as the definition I developed in another thread for you. The word "physical" describes the property of having predictable extrinsic relationships. This is borrowed from theory-physicalism, which excludes all instrinsic properties, making it meaningless to ask "What is an intrinsic property of physical things?" Mass is not an intrinsic property, so your own definition doesn't tell you what physicalness is by your own standards. Furthermore, massless particles are generally considered to be "physical."
 
  • #10
I think that the definition of what is physical evolves along with physics. Once upon a time when Descartes wrote, physical meant pushes and pulls by macroscopic matter, then there was gravity, and chemical bonds, conserved energy, and luminiferous ether, and so on. At each point people who espoused physical philosophies (Locke, Marx, the log-pos group) used the then current notion of physicality.

Today physicality pretty much means consistence with the Standard Model of particle interactions or with General Relativity (locally GR looks like Special Relativity so that is included too). Those theories are accepted by physicists as "effective", matching all experiments we know how to do now, and there is enormous experimental support for their predictions at all energy scales likely to be relevant to the human body.

People who use speculative theories beyond these have to carefully state their assumptions, and their conclusions can only be accepted modulo the theory they posit.
 
  • #11
selfAdjoint said:
Today physicality pretty much means consistence with the Standard Model of particle interactions or with General Relativity (locally GR looks like Special Relativity so that is included too).

Would the part of your post I selected be a concise definition? I would love to have a tight definition, one which states the absolute minimum needed to qualify as physical. That would help to judge if something is physical, or uf something is a trait of physicalness (a common dispute in debates). Let me give an example.

If I say one requires balance to ride a bicycle, can I then go on to say riding a bike is anything that requires balance? That sort of logic is what I don't like about the definition Loseyourname and StatusX give. They basically define physical as anything subject to logic and/or which obeys mathematical laws. I've disputed that because I don't see why some cosmic consciousness would not have particles and not be subject to relativity (using your definition now), and yet still have ordered aspects to it which could be represented logically or mathematically.

Let me ask you one thing more (well, it's several questions about the same thing). Do you think my definition is generally correct (that "physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass")? Do you think it automatically includes your elements (i.e., quantum and relativity factors)? Do you think it is more basic than your definition? Maybe too basic? If so, do you think my definition would be improved by adding yours, something like this:

"Physicalness is mass and the effects of mass, and exhibits consistency with the Standard Model of particle interactions or Relativity."
 
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  • #12
What a great question. Would the statement:

"Something is physical when it can be observed" be acceptable? Have I changed the game by rewriting the way the statement is said? "Physicalness" would then be something that is observable.

By the way, I don't personally consider your definition "that physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass" particularly good, because the concept of mass has become so exceedingly abstract and intermingled with other ideas. For example, light has no mass (though it has momentum) and yet I would consider it a physical thing. The fact that light can push seems to eliminate the possibility of it not being physical, and yet does not give it any mass.
 
  • #13
Locrian said:
By the way, I don't personally consider your definition "that physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass" particularly good, because the concept of mass has become so exceedingly abstract and intermingled with other ideas. For example, light has no mass (though it has momentum) and yet I would consider it a physical thing. The fact that light can push seems to eliminate the possibility of it not being physical, and yet does not give it any mass.

A photon has no rest mass. However, I understand what you are saying, which is why possibly the addition of inertia should be added to the definition. I've quoted the following before from the the McGraw-Hill Encyclopedia of Science and Technology: “The distinguishing properties of matter are gravitation and inertia.”

In terms of being observable as the definition, I don't think that tells us anything about physicalness itself; i.e., it's properties, nature, requirements for existence. Physicalness would still exist, for example, even if no one observed it.
 
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  • #14
Yes, but I didn't say something had to be observed to be physical, just that it had to be observ-able. One might argue that there are things that can be observed that aren't physical, such as love and anguish, but wouldn't a physicalist argue that those were, in fact, observable in a physical sense?

I still like my definition best. But then what do you expect? :tongue2:
 
  • #15
Les Sleeth said:
Would the part of your post I selected be a concise definition? I would love to have a tight definition, one which states the absolute minimum needed to qualify as physical. That would help to judge if something is physical, or uf something is a trait of physicalness (a common dispute in debates). Let me give an example.

If I say one requires balance to ride a bicycle, can I then go on to say riding a bike is anything that requires balance? That sort of logic is what I don't like about the definition Loseyourname and StatusX give. They basically define physical as anything subject to logic and/or which obeys mathematical laws. I've disputed that because I don't see why some cosmic consciousness would not have particles and not be subject to relativity (using your definition now), and yet still have ordered aspects to it which could be represented logically or mathematically.

Let me ask you one thing more (well, it's several questions about the same thing). Do you think my definition is generally correct (that "physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass")? Do you think it automatically includes your elements (i.e., quantum and relativity factors)? Do you think it is more basic than your definition? Maybe too basic? If so, do you think my definition would be improved by adding yours, something like this:

"Physicalness is mass and the effects of mass, and exhibits consistency with the Standard Model of particle interactions or Relativity."

First of all, I would accept the quote you selected as what physicalism means to me, and I would add an annex, not to add to but to explain that quote. Systems like electromagnetism and Newtonian physics are specializations of the standard model and general relativity, valid under certain retrictive conditions which conditions are generally true in the human body, including the brain (speeds are very tiny relative to c, and actions are very large relative to Planck's constant h). They can be used to specify physical states or phenomena if those conditions are met (and at least implicitly stated in the argument).

Secondly I would not like to see mass made fundamental to physicalism. In the standard model mass is a derived quantity (generated by the Higgs interaction and by the binding energy of gluons). Although mass in involved in some very interesting questions of broken symmetry (current work on neutrino masses comes to mind), it is not a reliable base to found a philosophic view upon. Energy (in the strict physical sense of the word) and momentum would be better for that purpose. But it would be instructive to read some of the physicists' answers to the Edge question "What do you believe that you cannot prove?" for further insights on this.
 
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  • #16
selfAdjoint said:
First of all, I would accept the quote you selected as what physicalism means to me, and I would add an anex, not to add to but to explain that quote. Systems like electromagnetism and Newtonian physics are specializations of the standard model and general relativity, valid under certain retrictive conditions which conditions are generally true in the human body, including the brain (speeds are very tiny relative to c, and actions are very large relative to Planck's constant h).

Secondly I would not like to see mass made fundamental to physicalism. In the standard model mass is a derived quantity (generated by the Higgs interaction and by the binding energy of gluons). Although mass in involved in some very interesting questions of broken symmetry (current work on neutrino masses comes to mind), it is not a reliable base to found a philosophic view upon. Energy (in the strict physical sense of the word) and momentum would be better for that purpose. But it would be instructive to read some of the physicists' answers to the Edge question What do you believe that you cannot prove? for further insights on this.

I am in a hurry now, so I'll have to wait until tomorrow to think about all your comments. But just one point.

The definition I gave using mass was meant to say that physicalness isn't just anything with mass, but it is also that which is derived from mass (i.e., which now might be massless) and that which is manifested by the effects of mass present (such as gravity). Where I'm coming from with that is, basically, the Big Bang. It seems to me that that's what the BB primarily did -- create mass -- and then everything has emerged from and been manifested by that.

What do you think of my thinking :tongue2: in this respect?
 
  • #17
Locrian said:
Yes, but I didn't say something had to be observed to be physical, just that it had to be observ-able. One might argue that there are things that can be observed that aren't physical, such as love and anguish, but wouldn't a physicalist argue that those were, in fact, observable in a physical sense?

Yes, but you aren't defining physicalness. You are describing human perception. What I am after is the properties of physicalness itself which something must minimully possesses to be recognized as physical.
 
  • #18
We shouldn't just freeze physicalsim at what we know now (GR and the Standard Model), since, as SelfAdjoint pointed out, the definition of physicalism has changed as science has progressed. It seems you are trying to define physicalsim so that the things you believe to be unphysical, such as consciousness, remain so. I think "physical" should be defined from a social point of view: having the capacity to be investigated and explained by science. It seems pretty clear what is scientific and what isn't, and as science expands, so will the realm of the physical.
 
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  • #19
Apologies for being repetitive, but I am defining physicalness; I am saying it is dependant upon human observation. I'm unwilling to replace the word "observation" with "perception" and do not understand why you did that. Observability is the most fundamental property of physical to me. When you ask if something is physical, that may very well be the only property I consider.

I would disagree with Self Adjoints definition of physicality on the grounds that it is circular and temporary. Defining something as physical because we currently have a predictive system that can predict things about it to me seems backwards. We generated that system (GR or SM) by observing physical things. Using that system to then define what it is for something to be physical seems to me rather backwards. On top of that, we are almost certainly to make advances in physics that would require his definition to be rewritten for the new ideas.

So why am I not giving you want you want? I don't feel particularly new to this conversation, but the responses to my posts seem to suggest - respectfully - that I'm somehow missing the point. I am more the willing to admit I may be doing that, but I just don't understand why or how.
 
  • #20
Les Sleeth said:
I am in a hurry now, so I'll have to wait until tomorrow to think about all your comments. But just one point.

The definition I gave using mass was meant to say that physicalness isn't just anything with mass, but it is also that which is derived from mass (i.e., which now might be massless) and that which is manifested by the effects of mass present (such as gravity). Where I'm coming from with that is, basically, the Big Bang. It seems to me that that's what the BB primarily did -- create mass -- and then everything has emerged from and been manifested by that.

What do you think of my thinking :tongue2: in this respect?

According to what is called the standard model of cosmology (not to be confused with the standard model of particle physics), immediately after the big bang there was no mass; the forces were all unified and the particles had not condensed out of the energy. In general relativity mass is only one of the sources of energy and momentum which warp spacetime; light, which has momentum but no mass, is another. Gravitational waves are still another.

Paul Davies has a book called The Matter Myth which discusses some of these ideas.
 
  • #21
Would a definition including observability and parsimony be acceptable?
For instance, "an object is physical if it can be directly observed or postulated as the cause of an observable effect in a system where each physical effect has one and only one physical cause and direct observation is a physical effect," or something along those lines.
 
  • #22
Les Sleeth said:
If I say one requires balance to ride a bicycle, can I then go on to say riding a bike is anything that requires balance? That sort of logic is what I don't like about the definition Loseyourname and StatusX give. They basically define physical as anything subject to logic and/or which obeys mathematical laws. I've disputed that because I don't see why some cosmic consciousness would not have particles and not be subject to relativity (using your definition now), and yet still have ordered aspects to it which could be represented logically or mathematically.

But we didn't say "physical" meant "subject to relativity." We said it meant "subject to mathematical predictability." It still seems the only reason you don't like this is because you want a definition that excludes your conception of consciousness.

To go with your bike analogy. It takes balance to ride a bike, but not all balancing acts are riding a bike. Works fine for riding a bike. But with the word "physical," all mathematically predictable phenomena are physical. This is not logically derived. It is just this way by definition. This might be the most succint definition I can give:

Any phenomenon is physical if and only if it displays extrinsic relationships that can be mathematically modeled.
 
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  • #23
I've long had a favorite definition of physicality. "Physical things are only those things which exert influence over some physical things." To put this into action you assume that some particular things are physical, such as basketballs, and everything which influences them is physical. Physicality by this definition is exactly what someone trying to predict some physical event must consider.

Dualists like to say that physicality is more limited than this, because if the soul has any influence on the physical world, then the soul itself must be physical by this definition. Dualists generally say something that boils down to, "physical things are only those things which fall under (the previous definition of physicality) but are not of the spirit."

I dislike this definition because according to it, physicists, in trying to predict things, must sometimes consider non-physical things.
 
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  • #24
Les Sleeth said:
Debates about physicalism are sometimes hampered because participants can't seem to agree what "physical" is. I'd like to invite all physicalists and those who believe they are clear about what physicalness is to create an exact definition.

I'll offer my opinion first. I think physicalness is mass, immediate effects of mass, and all that which has come about from the presence of mass. Since all mass we know of is believed to have originated with the Big Bang, then I'd also restrict the definition of physical to how mass and mass effects have developed from that event.

In a past thread I posted the following in support of my definition:

Princeton's Word Reference site give the definition of physical science here:

- the science of matter and energy and their interactions


On the same page you can find a definition for physicalness:

- the quality of being physical; consisting of matter


The Word Reference site gives several relevant definitions of physical here:


1* physical - involving the body as distinguished from the mind or spirit . . .
2* physical - relating to the sciences dealing with matter and energy; especially physics; "physical sciences"; "physical laws"
3* physical, tangible, touchable - having substance or material existence; perceptible to the senses; "a physical manifestation"; "surrounded by tangible objects"
4* physical - according with material things or natural laws (other than those peculiar to living matter); "a reflex response to physical stimuli"
6* physical - concerned with material things; "physical properties"; "the physical characteristics of the earth"; "the physical size of a computer"


Of Physicalism the Wikipedia says:

Physicalism is the metaphysical position that everything is physical; that is, that there are no kinds of things other than physical things. Likewise, physicalism about the mental is a position in philosophy of mind which holds that the mind is a physical thing in some sense. This position is also called "materialism", but the term "physicalism" is preferable because it does not have any misleading connotations, and because it carries an emphasis on the physical, meaning whatever is described ultimately by physics -- that is, matter and energy.


All these definitions are all well and good. They cause more confusion than they produce knowledge, if any. They cause more problems than they solve. Just imagine living in a world where everyone speaks one language and every word in the dictionary has only one meaning? Imagine what the world would look like. All these definitions that you have invoked from various sources reiterates and reinforces my earlier call in some of the threads on this PF for all these terms to be revised and given a commonly accepted definitions and connotations. 'MATTER' and 'PHYSICAL' are good examples of these terms. In terms of the notion of 'Physical', the very simplest and the most basic meaning of it is 'ANYTHING YOU CAN SEE'. The problem arises form limiting the meaning of the term 'SEE' to anything that we see with our eyes only. But supposing we extend the notion of see to include all the five senses?

The questions that new generations of philosophers are now asking are these: what would happen to the whole system of the human perception if all the visual organs in a human body were scientifically reduced to one single visual organ? How would this be engineered into the body? And let's say this was possible in the first place, how would we see and interprete the world? Would we end up with a new reality? Ultemately, would the multi-partite self still exist?

Ok, what about these?

When you see with your eyes, are you seeing?
When you hear with your ears, are you seeing?
When you smell with your nose, are you seeing?
When you feel with your skin, are you seeing?
When you taste with your tongue, are you seeing?
When you introspect, think or reason, are you seeing?


And ultemately,

When you use scientific instruments or any known visual aids or extensions, are you seeing?

On the other hand, if the human still remained in its present state with its present multi-partite configuration, sooner or later we would have to come to a common definition and understanding of what it really means for something to be physical. My own observation up to now is that we are mistaking our own visual limitations for something over and above the physical. We are failing to take our visual and sensual limitations into account of the problem. As I have observed everywhere in this forum, it seems that when something is beyond the range of the human observation, we give it a different name and think of it as being something else. The question that will continue to haunt our conscience for a very long time to come is this:

If the human physical or material body extends beyond what we can see and fully explain, does it stop being physical from this point, given that we knew what the term 'physical' really stands for in the first place?
 
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  • #25
I've long had a favorite definition of physicality. "Physical things are only those things which exert influence over some physical things." To put this into action you assume that some particular things are physical, such as basketballs, and everything which influences them is physical. Physicality by this definition is exactly what someone trying to predict some physical event must consider.

It's a little dangerous, though, as a definition since some physical events seems to disobey cause-and-effect. But it would be the definition I prefer too, so long as we include influences like altering probabilities, as well as direct stuff.
 
  • #26
StatusX said:
I think "physical" should be defined from a social point of view: having the capacity to be investigated and explained by science.
loseyourname said:
Any phenomenon is physical if and only if it displays extrinsic relationships that can be mathematically modeled.
Bartholomew said:
Physical things are only those things which exert influence over some physical things.
honestrosewater said:
. . . an object is physical if it can be directly observed or postulated as the cause of an observable effect in a system where each physical effect has one and only one physical cause and direct observation is a physical effect.
Locrian said:
I am saying it is dependant upon human observation. . . . When you ask if something is physical, that may very well be the only property I consider.

In my humble opinion, all you guys are confused about what it means to define. When it comes to something as substantial as physicalness (i.e., not something abstract like justice, love, infinity, etc.) it means to establish the boundaries and nature of, what something IS. None of the above definitions capture the existence of physicality, but rather they are either some trait of physicalness, or they are recognition, investigation or calculation techniques.

What if I’d said, “define Earth’s atmosphere.” So one of you says atmosphere is anywhere I can breathe; another says, atmosphere is a chemical mixture; another says, atmosphere is a gas; another says, atmosphere is what makes my gauge register “atmosphere.” A meteorologist might say, “Earth’s atmosphere is the mixture of gases surrounding the planet whose percentages in its lowest layer are 78% nitrogen, 21% Oxygen, 1% argon, with small quantities of other gases such as carbon dioxide and water, whose pressure . . . etc.” Now that is a definition of something we know exists.

Physicalness exists, it has properties, it has its own is-ness. What ever it IS, it is not determined by sense perception, or by math, or by society . . . Observationability is not a property of physicalness because physicalness doesn’t require human consciousness to exist! Observation is a property of consciousness, and science and math are skills of consciousness.


StatusX said:
It seems you are trying to define physicalism so that the things you believe to be unphysical, such as consciousness, remain so.
loseyourname said:
It still seems the only reason you don't like this is because you want a definition that excludes your conception of consciousness.

This is not a fair assessment. I might reply you two are just trying to find a way to claim everything is physical. It is true that I know of something, through my personal experience and which I have studied the history of, which is not explained by any physical principles I've heard. It is also true that every physicalist I've ever talked to and debated has known absolutely nothing about this subject. So their attempts at sweeping generalizations about reality is missing a key element, IMO, which is not explained by any physical model or definition.

To me whatever physical is for our universe started with and came from the Big Bang. However, something had to exist before the BB, some sort of primordial potentiality (whether that’s foam-like space time or illumination or whatever) which could cause the BB. But here’s the deal: consciousness might have developed out of that primordial potentiality as well. And that is the distinction for me. In other words, consciousness might have arisen straight out of primordial, pre-BB conditions, and not from the “physical” conditions determined by the Big Bang. So the basis of my concern for defining physicalness is: which developed first out of primordial conditions, consciousness or the physical universe?

Back to the issue of defining physical. After taking into account selfAdjoint’s comments, I would say “physical” is the most fundamental universal conditions that the Big Bang has produced, and that has two aspects:
1. Matter.
2. The effects of matter.

Let’s see if I can defend that definition.

According to the commonly accepted theory, 10 -43 seconds after the Big Bang was the so-called GUT epoch; so there was nothing yet that could be called matter, as selfAdjoint pointed out. At 10 -20 seconds after inflation, most of what would be required to form matter existed; EM and weak forces separate, quarks form protons and neutrons. But a mere 3 minutes after the Big Bang the first nuclei were synthesized. Since expansion and cooling were going to continue, the rest of the matter of the universe was virtually guaranteed to develop.

Okay, two points. Wasn’t that which was to give our universe its most substantial characteristics already forming well within the first second of its existence? Also, consider how much of what we observe today in the universe is the result of, or has resulted from, the presence of matter (I’m not sure where background radiation fits in).

Take the two most influential aspects of the universe, quantum mechanics and relativity. Would they mean anything without matter? One might say gravity is independent of matter, but is it? If there were no matter (or at least something with mass), we’d never know if gravity existed. Radiation, neutrinos, heat, energy, expansion, force, TIME . . . our universe’s character seems completely determined by the presence, and lack, of matter. Without matter there would be no substance, and there would be no effects; no QM, no observable gravity, no movement or change.

So I say, regardless of what the universe once was (and will become), from a few minutes after its origin to right now, physicalness has been most determined by matter itself, the effects of matter (e.g. gravity), the change/movement of matter (e.g. inertia), and the offspring of matter (e.g. radiation).
 
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  • #27
The state of being matter--massiveness--is only a certain property of things that helps describe how they move. Why single that property out over others?
 
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  • #28
Les Sleeth said:
In my humble opinion, all you guys are confused about what it means to define. When it comes to something as substantial as physicalness (i.e., not something abstract like justice, love, infinity, etc.) it means to establish the boundaries and nature of, what something IS. None of the above definitions capture the existence of physicality, but rather they are either some trait of physicalness, or they are recognition, investigation or calculation techniques.

What if I’d said, “define Earth’s atmosphere.” So one of you says atmosphere is anywhere I can breathe; another says, atmosphere is a chemical mixture; another says, atmosphere is a gas; another says, atmosphere is what makes my gauge register “atmosphere.” A meteorologist might say, “Earth’s atmosphere is the mixture of gases surrounding the planet whose percentages in its lowest layer are 78% nitrogen, 21% Oxygen, 1% argon, with small quantities of other gases such as carbon dioxide and water, whose pressure . . . etc.” Now that is a definition of something we know exists.

The problem is, we know every important detail about the atmosphere, but not about the physical world. To continue your analogy, imagine if the ancient greeks tried to define the atmosphere. They obviously couldn't use your defintion, so what could they come up with? Maybe something like "that which is between the Earth and space." This isn't precise, as it depends on where "the earth" ends and where "space" to begins, but it's about the best they could be expected to do. Similarly, we are not yet capable of a precise definition of physicality. That is why I suggested my definition, that it should be defined as that which science can explain.

For all we know, mass is just a special case of a more fundamental property that the final theory of physics will be based on. Maybe there is some quantifiable property that all "stuff" in the universe has, and when this property has a certain value, that stuff is matter. Most of what we can observe has this value, so we think everything is matter. But does that mean the other stuff is non-physical, even though it falls under this theory? This may sound like an exageration, but actually, string theory predicts all "stuff" is just strings, and the property of having mass just corresponds to a certain vibrational pattern. String theory isn't necessarily correct, but it shows that cutting off physicality at "that which has mass" or even "that which is affected by mass" is probably too limiting. But my defintion is sort of like the elastic clause of the constitution, and it doesn't have this problem. Once we have a final theory, we'll be in a position to make a more concrete defintion of physical.

To me whatever physical is for our universe started with and came from the Big Bang. However, something had to exist before the BB, some sort of primordial potentiality (whether that’s foam-like space time or illumination or whatever) which could cause the BB. But here’s the deal: consciousness might have developed out of that primordial potentiality as well. And that is the distinction for me. In other words, consciousness might have arisen straight out of primordial, pre-BB conditions, and not from the “physical” conditions determined by the Big Bang. So the basis of my concern for defining physicalness is: which developed first out of primordial conditions, consciousness or the physical universe?

I'm sure you realize time started at the big bang just like space, so you'll have to be more specific on what you mean by "which came first."
 
  • #29
Bartholomew said:
The state of being matter--massiveness--is only a certain property of things that helps describe how they move. Why single that property out over others?

But see, if you don't represent what I said, then this won't work. I did not only say the "state of being matter." I included (and actually I suspect this is more influential in our universe) ". . . the effects of matter (e.g. gravity), the change/movement of matter (e.g. inertia), and the offspring of matter (e.g. radiation)."

What "other" important property have I not included? Keep in mind, my point is that matter, its effects, and its derivations are determining the most significant aspect of the universe.
 
  • #30
StatusX said:
The problem is, we know every important detail about the atmosphere, but not about the physical world. To continue your analogy, imagine if the ancient greeks tried to define the atmosphere. They obviously couldn't use your defintion, so what could they come up with? Maybe something like "that which is between the Earth and space." This isn't precise, as it depends on where "the earth" ends and where "space" to begins, but it's about the best they could be expected to do. Similarly, we are not yet capable of a precise definition of physicality. That is why I suggested my definition, that it should be defined as that which science can explain.

I don't think you've addressed the issue at all. It isn't a matter of what one knows, the analogy wasn't about that. It was thinking what the abilities and limitations of human consciousness can or cannot perceive has anything to do with the existential qualities of matter.

StatusX said:
For all we know, mass is just a special case of a more fundamental property that the final theory of physics will be based on. Maybe there is some quantifiable property that all "stuff" in the universe has, and when this property has a certain value, that stuff is matter. Most of what we can observe has this value, so we think everything is matter. But does that mean the other stuff is non-physical, even though it falls under this theory? This may sound like an exageration, but actually, string theory predicts all "stuff" is just strings, and the property of having mass just corresponds to a certain vibrational pattern. String theory isn't necessarily correct, but it shows that cutting off physicality at "that which has mass" or even "that which is affected by mass" is probably too limiting. But my defintion is sort of like the elastic clause of the constitution, and it doesn't have this problem. Once we have a final theory, we'll be in a position to make a more concrete defintion of physical."

Well, I'm not sure string-ness is physical. What if stringness existed before the Big Bang? Maybe that is part of the primordial condition I mentioned. The issue is, can consciousness arise out of primordial conditions, or must it have a Big Bang physical universe first to appear?


StatusX said:
I'm sure you realize time started at the big bang just like space, so you'll have to be more specific on what you mean by "which came first."

Physical time started with the Big Bang. The "space" between physical objects developed after the Big Bang. I once again reference you to my above objective for distinguishing between physcial and non-physical.
 
  • #31
I think the point of confusion is whether physicalness is either an object or a property of objects.
 
  • #32
honestrosewater said:
I think the point of confusion is whether physicalness is either an object or a property of objects.

Well, I don't think you can go to the museum to see an example of physicalness, up on its pedestal, so I suspect its a property; for Chalmers it seems to be the property of things that physical science is capable of studying and that consciousness (says Chalmers) transcends.
 
  • #33
How about an interaction between massless particles, generating new massless particles? Would you consider these new massless particles physical ("offspring of matter") or not? I am guessing that you would, but if you do then all you're saying is that the particles were at one time in the form of matter. At other times they were in the form of energy. So what?

Any way you look at it, you're singling out the property of being matter over other properties. The things in front of you seem most "real" to you because you can see them and pick them up and interact with them in other useful ways, but this has no cosmic meaning. Energy, too, is real. Why not say something like, "the physical world is energy, the effects of energy (e.g. gravity), the change/movement of energy (e.g. heat), and the offspring of energy (e.g. matter)"? Energy may seem "ethereal" to you but it is just more stuff which happens to have different properties.
 
  • #34
You'll still trying to look for intrinsic characteristics of physicalness. I'm trying to tell you that physicalness is not defined by intrinsic properties. In fact, being massive and having inertia and all these others things are not even intrinsic properties besides. If you bought that Rosenberg book we're going to be discussing, perhaps you'll understand the way he explains it better than the way I do. As far as I can tell, physicalness is defined by having extrinsic properties that can be mathematically modeled. It makes absolutely no difference what the intrinsic properties of these physical things are. As hypnagogue has explained in other threads, there are two different conception of physicalness. One actually does include intrinsic properties, and is called object-physicalism. This brand of physicalism, however, is very rare and doesn't have many adherents. Most physicalists are theory-physicalists, who only hold that extrinsic properties are physical. To explain again why I only include objects with extrinsic properties that can be mathematically modeled, I'll again appeal to the study of physical things: physics. If a given phenomenon can be studied by physics (that is, it can be mathematically modeled), then it is physical.

This seems to do it for me. I've given all of the necessary and sufficient conditions for a thing to be considered physical. If that isn't a definition, what is? Consider this: Any given word a refers to object b if object b has the set of properties {x1,x2, . . . xn} that define word a. Is that not the proper form of a definition? Substitute "physical" for a and use "has extrinsic properties that can be modeled mathematically" for the set of necessary and sufficient conditions that define a.
 
  • #35
I don't think that mathematical modeling is a good way to approach it either. For example, there is a theoretical limit to computational power; a computer powerful enough to model everything that goes on in the universe would not fit in the universe. And random phenomena, if there are such things, can't be modeled mathematically either. In those two situations the best you can do is approximate, "halfway" modeling.
 

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