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Look at what I've just read on the Internet Encyclopedia of Philosophy: "There are no laws of nature that hold just for the planet Earth (or the Andromeda Galaxy, for that matter), nor are there any that hold just for the Eighteenth Century or just for the Mesozoic Era." I agree that this looks absolutely true, but why is it so? I suppose science cannot prove that there is no fundamental law of physics that holds only in a small part of the universe or only during some short period. Sure, such a law would be unexplainable, at least scientifically unexplainable, but aren't ALL fundamental laws of physics unexplainable? That's why they are fundamental. If the above quotation is only stipulating some meaning of "laws of natures", isn't it arbitrary? Thank you.

I just wanted to add to Allen's remarks (with which I largely agree). First, the claim that there are no laws of nature that hold just for (e.g.) the planet Earth may require the qualification "no fundamental laws of nature". After all, if it is a law of nature that like electric charges repel, then it is a law of nature that like electric charges on planet Earth repel. The latter is a derivative law, however. So there could easily be non-fundamental laws that hold just for the planet Earth. Second, on Lewis's own version of the Best System view, the laws of nature must all be truths. There is no trade-off between "complete and perfect truth" and "greater generality." Of course, a modified version of Lewis's account might be more liberal. Third, it could be that all fundamental laws of physics have no explanations (that's what makes them fundamental, as you say), and yet there is a reason why all fundamental laws of physics cover all of space-time and (to put it roughly) say the same things...

The standard way of thinking about 'mental disorders' goes like this: Take some phenomena and think of a name that stands for all phenomena together. So far nothing wrong. But then it happens, the given name is being crowned as cause of the phenomena... as in the expression; "depression causes low self esteem, a sense of emptiness,..." while depression is just a given name for all those phenomena. To me that seems as an insult to the laws of logic. Can someone state a logical proof that this way of thinking is against logical laws?

If a mental disorder referred simply to a collection of symptoms, then it could not be a cause of those symptoms. You are exactly right about this. A cause must be distinct from its effect. That is why we cannot say that my slamming the door was a cause of my shutting the door (where "slamming the door" is nothing more than shutting the door with some force). However, it is not at all obvious that the name of a mental disorder is simply the name for a collection of symptoms. On the contrary, the mental disorder's name might refer to a certain kind of cause of those symptoms -- perhaps a cause that is not yet identified at the time that the mental disorder was named. Then when the cause is later discovered, it is understood what the name of the mental disorder was referring to all along. Thus, a mental disorder can be a cause of some phenomena because it is distinct from those phenomena. The very same idea applies to the names of somatic (i.e., non-mental) disorders. A new illness (such as...

I have a question about the entities in scientific theories and models. The status of some of these objects seems intuitive. Frictionless planes, for example, though they don't exist, seem helpful enough as an abstraction for understanding how actual planes function. My question is about entities which we (non-scientists) know only through the prism of scientific theory--say, photons or electrons. I know what light and electricity are, on some immediate level, through my everyday experience of these phenomena. But I don't know what to make of the entities that physics tells me compose them. My inclination is to take them as "real", not just convenient notions of the purpose of theorizing and mathematical models. I can't help pictures these tiny, planet-like spheres whizzing around. I know there's something importantly wrong about that image, but I'm not sure what. Furthermore, scientists still talk about particles "spinning" and so forth, I am unable to see in what sense this is an analogy in the way...

The question that you are raising is a venerable and perennial one. In the trade, it is called the dispute between "scientific realism" and "scientific anti-realism." Scientific realism is the view that in science, when a theory is accepted, the unobservable entities that the theory posits are believed to exist and the theory's statements about them are believed to be (approximately) true. Scientific anti-realism is the view that in science, when a theory is accepted, the theory's claims about observable facts are believed to be true, but the theory's claims about unobservables are not believed to be true. Rather, they are believed to make accurate predictions about observables. That is all that science requires of its theories about unobservables. In your question, you alluded to Ptolemy's epicycles. This is a perfect case in point. In the ancient world, the celestial spheres posited by astronomical theories as carrying the planets along in their orbits (around the earth) were widely regarded not...

I've been in education of some kind for over fifteen years now, and over these years I've had many history classes, concerning a variety of topics. Something strange happens in all of them, though - without exception, the classes never seem to spend more than a single session on anything that happened after the 1950s. In high school, we had a single class to talk about the Cold War; two other years of history didn't even go that far, except in the broadest of strokes with mentions of decolonialism. In a college course on American history, our last session was the origins and beginnings of the civil rights movement, with nothing beyond that. The social, technological, political and ideological shifts in the past half-century seem to be deemed unworthy of teaching. Why is this? Aren't the social and technological developments of the last sixty or seventy years at least as critical to the understanding of modern society as the sum of all that came before? What is the importance of teaching the history...

I agree entirely with the general point that you are making. I think that the events of the last 60-70 years are worthy of discussion in high-school history classes. Although I don't really know how to measure whether they are "at least as critical to the understanding of modern society as the sum of all that came before", I'll admit that they are pretty darn critical. I don't think that the reason that relatively recent events are less often taught in history courses is that they aren't believed to be important. There are many possible explanations for the relative neglect of recent history in high-school history classes. One is that there is so much older history to get through that teachers do not leave enough time for recent events. Another is that recent events are so much more controversial than earlier events that it is difficult to write textbooks that will be approved by school boards that cover these recent events. Another is that the overall significance of recent events is not yet entirely...

I consider myself a (metaphysical) materialist or, to use the synonymous term that is more fashionable nowadays, physicalist, and I'm familiar with the academic literature on contemporary materialism/physicalism. But in no paper or book did I find really satisfying, fully adequate definitions of the central concepts of a material/physical object and of a material/physical property. (A material/physical property certainly isn't material/physical in the same sense as a material/physical object.) Does this mean that there actually aren't any such definitions, and that materialism/physicalism is therefore a virtually vacuous doctrine? Material/physical objects (substances) could be defined in terms of material/physical properties: x is a material/physical object =def x has some (intrinsic) material/physical properties. But then the big problem is how to properly define the concept of a material/physical property. I've been trying to devise and formulate a fully adequate definition of it for several years...

This is indeed a difficult question. If we say that a physical object is an object with intrinsic physical properties, then you are right: we have left ourselves with the question of what a physical property is. If we say that a physical object is an object with spatiotemporal properties (such as position and velocity), then someone who believed in irreducible minds or souls that have spatial locations could presumably still count as a physicalist, which seems inappropriate. If we say that a material object is an object that is made of matter, then we need an account of what matter is. Are electric fields made of matter? They have mass, after all. Would Newtonian space be made of matter? It doesn't seem like it would be ... but its existence does not compromise materialism, does it? More generally, materialism and physicalism seem to be motivated by the idea that the entities described by physics are all of the entities that there are -- or, more precisely, are all of the fundamental entities there...

It has recently struck me that despite my interest in both physics (as a qualified physicist) and philosophy (as a complete amateur), I have not encountered any philosophy regarding the 'origin' of the universe or indeed aspects of the Cosmos as a whole. While metaphysics is increasingly dealing with questions and dilemmas in modern theoretical physics, I have not seen anyone address the question of *why* the Universe/Cosmos exists. I raise this point purely from a metaphysical standpoint. (The religious aspect is irrelevant.) I am curious whether most philosophers would even think it is a valid question to ask *why* the Universe exists. That is, why not nothing? (I do not mean the Universe is a limited physical sense, as part of a great "Multiverse" perhaps, bus as the all-encompassing everything.) If it does not sound too strange: why does nothing not exist? The temporal problems that some consider; for example the "beginning" and "end" of time do not particularly bother me as a scientist, since time...

There is a considerable literature on this subject. As a place to start, I suggest "Why anything? Why this?" by Derek Parfit, reprinted in "Metaphysics: a guide and anthology" edited by Tim Crane and Katalin Farkas (Oxford University Press, 2004), as well as the discussion of this question in Robert Nozick, "Philosophical Explanations" (Harvard, 1981) -- a large book that touches on many other topics besides this one. Further references can be found in those places. Also relevant are several papers by Adolf Grunbaum and Dean Rickles. There is also a story that Sidney Morganbesser was asked why there is something rather than nothing and replied, "Suppose there had been nothing. You wouldn't have been happy then either!"

Recently I was watching the famous "Powers of Ten" video which starts with a couple at a picnic and moves out to the far edges of the universe, moving ten times further out each second. After this the camera goes back to the couple and enters the hand of the man at the picnic, moving through layers of skin, blood cells, molecules, atoms and finally a haze of interacting subatomic particles. What struck me about this part of the video is that if the camera was to move beyond the boundaries of the man's hand we wouldn't be able to tell. There is no demarcation between the subatomic particles which make up the man's hand and the subatomic particles which make up the surrounding air. So, in what sense do seperate entities exist? Is seperateness an illusion inherent to the experience of beings at a macroscopic scale, similar to our illusion that objects are "solid" when in reality an atom is comprised mostly of empty space?

I love that video! Thank you for your excellent question. Of course, you are correct in saying that there is no sharp demarcation between the hand and its air around it. A water molecule that is part of the hand may at some point evaporate into the surrounding air. There is no particular moment at which the molecule leaves the hand and becomes part of the atmosphere. Its chemical bonds to other "hand" molecules weaken gradually, its distances from those molecules increase gradually, and even if these quantities do not change continuously (in the mathematical sense), there is no magic bond strength or distance at which the molecule officially leaves the hand and joins the air. That being said, the fact that there is no sharp distinction does not guarantee that there is no distinction at all -- that "separateness is an illusion inherent to the experience of beings at a macroscopic scale". After all, there is no sharp distinction between night and day -- yet night is not the same as day. It...

I asked this question of a physicist and he told me to ask a philosopher. If one was to observe a closed, isolated region of space under vacuum conditions, i.e. there are no particles in this region and none may enter into it. Also there are no fields (i.e. gravitational, electromagnetic, etc.) acting or existing on or in this region. The only interaction with this system is as an outside observer. Can this observer notice the passing of time? If so, how? And does the act of observation make the observer part of the system, since the observer is technically interacting with it? Currently we measure time by the movement of quantum mechanical particles, such as the molecules in a ticking clock; the vibrations of atoms; and the decay of radioactive isotopes. But could we perhaps, in this hypothetical system, justify using properties of space itself, such as quantum foam or the expansion of space (expanding universe), and, if so, how would we observe these features?

Thank you for your question. Let me touch it up just a bit: There are no gravitational fields in general relativity over and above the curvature of space(time). In the spirit of the question, I will assume that the spacetime geometry is unchanging. An observer might be able to notice the passing of time in lots of ways (e.g., from his own heartbeats or passing thoughts or wristwatch). I presume that the question is asking whether the observer could notice it on the basis of some observed changes in the region of space in question. I am inclined to think not. Nothing is changing there. If spacetime geometry were changing, then the passage of light through the region to us would betray the change to us. But the question stipulates that nothing passes through the region.

Hey there! My question is: is randomness an illusion or can everything theoretically be predicted? Let me use the coin toss analogy. At first, a coin toss appears totally random, but as we look deeper, we find that the "randomness" is simply a result of factors that we cannot perveive at first glance (ie. tossing force, distance from ground, air resistance etc). Suddenly the coin toss isn't random anymore. So is true randomness really out there or is all randomness just an illusion?

That's an excellent question. Here is a rough reply. Oftentimes, when we refer to some everyday phenomenon as "random", we mean that we are ignorant of the fundamental causes at work -- as in games of chance. However, according to modern physics, there are some fundamental phenomena involving the behavior of sub-atomic particles that are genuinely random. For example, if a radioactive atom existing now has a half-life of (let's say) 100 seconds, then there is a 50% chance that it will decay sometime during the next 100 seconds, and there is no feature that the atom has now (or that anything else has now) that determines whether the atom will decay or won't decay. It is an irreducibly random process. In other words, the atoms that ultimately do decay before 100 seconds have passed are no different now from the atoms that do not decay during that interval. There are no "hidden variables" to distinguish them. I should add that the reason we have for believing that these phenomena are genuinely random...

We know that when we see Alpha Centauri with the naked eye we are seeing light that left that star over 4 years ago when Bush was still President. Other stars are obviously much farther away and we’re looking at light that originated, say, when Galileo was still around or when the pyramids were being built. When we’re told that telescopes help us see into ‘deep space’ I’m wondering what that means: do they simply magnify the detail of images or do they help us see the detailed images earlier than we would with the naked eye? The difference that I have in mind is this: a friend comes to my house who I know has been travelling an hour to see me. I first see him when I open the front door. But suppose I’m looking forward to the reunion and I set out to meet him half way so as to abbreviate his journey. Suppose further I have the capacity/technology to meet him at his place of origin so I can see him immediately. Now, does a telescope, say Hubble, allow astronomers and cosmologists to see ‘earlier’ into...

A telescope collects more light than an ordinary human eye. It is a larger "light bucket". Consequently, a telescope helps us to see things that are fainter (as seen from earth) than we can with the naked eye. Consequently, a telescope helps us to see things that are more distant (and hence helps us to see things as they were longer ago). A terrestrial telescope does not "meet" light somewhere along the way, unfortunately. The light must still manage to arrive at Earth.

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