So does science. Science and Philosophy are about things. Is the idea of multiple universes and dark matter in the domain of philosophy or science? Are they mental entities as bongo put it, or something else?If they're about things in the world, they're fine. It's mainly philosophy that tries to comment on the world from a vantage point external to it. — Tate
Depends on the claim. Maybe the issue is saying that you can claim any metaphysical position. Seems that you can only ponder or hypothesize metaphysical positions. A claim would change it from being metaphysical to scientific, no? Are scientific claims nonsense? Why?That metaphysical claims are nonsense. — Tate
If we dispense with mental entities then what is left?That's the kind of reason I (and I claimed also W) counselled dispensing with mental entities.
I was going along with it (entities included) out of interest, while I thought I could follow. Awareness too, and I'm out of here. — bongo fury
And then lost traction when science discovered that the world is not as it appears and that observers might actually influence what is observed.It gained traction with advancements in the natural sciences which heavily depended on observation and repeatability as a ground for establishing fact verses hypothesis or beliefs. — Benj96
So physicalism, materialism and naturalism are concepts. How are concepts physical, material or natural? How do physical things and concepts interact, or how do physical things come to possess concepts?To my mind, methodologically speaking, materialism (facticity, data) is a subset of physicalism (modeling) which is subset of naturalism (explanation). — 180 Proof
Sounds circular. What does it even mean for a concept to be physical vs. Non-physical? Are you talking about the ontology of concepts, or what the concepts are about? If the latter how do concepts come to be about anything? Is aboutness physical or non-physical?As a metaphysics, it's arbitrary, even scientistic. However, as a methodology (criterion) for eliminaing "nonphysical" concepts from the construction of explanatory models of phenomena, physicalism is demonstrably more useful than any non/anti-physicalist alternative. — 180 Proof
Everyone examines their lives at some point - usually in the late teens - early twenties. They question their existence and their purpose. The real question is how much of an examination does your life need before you can get on with just living it? Philosophy seems to have shown that you can never know anything, or that you have to start with some assumptions. So it would be pointless to keep asking questions for which you will never get an answer.Interesting argument. I didn't ask or answer any such questions in 4th grade. I think most of us live unexamined lives, derive value systems unsystematically through experience and socialisation, holding onto views that are an amalgam of fallacies, prejudices and models of reality which can't be justified. I think the point is ignorance is bliss, truth seeking doesn't ususally make any real difference to survivability or prosperity and people have no idea how much of what they think is deficient. — Tom Storm
Philosophers are the ones that don't seem to realize that as they attempt to re-ask the same questions we asked and solved in the 4th grade.
— Harry Hindu
What are those questions? — Jackson
They weren't cherry-picking past usage. Read your sentence again. They were re-purposing words, which are scribbles and utterances, for new usages, just like we re-purposed bumps to use as words as braille, and arm and hand movements as sign-language.When we agree on new uses for a term we are essentially creating a new context with which we use the term.
— Harry Hindu
Sure. Cherry-picking cases of past usage that help to sell our new theory.
Weren't Newton & co. rather cheekily re-purposing psychological words like force ("courage, fortitude"), inertia ("unskillfulness, ignorance"), moment ("importance")? — bongo fury
Sure, there are some uses of language that appear to be habit more than a clear understanding of what it actually means to say such things, but I've seen philosophers fall prey to the habit just as much as ordinary people. Assumptions make up the the foundation from where we build our understanding of the world. Philosophers are the ones that don't seem to realize that as they attempt to re-ask the same questions we asked and solved in the 4th grade. That isn't to say that there aren't some higher level assumptions that we take for granted that can't be questioned - like does God exist - but then ordinary people can be just as concerned about whether god exists (like when they are suffering at the hand of an unfair world) as a philosopher can.To finish the preface: the philosopher believes that the ordinary person is either unfamiliar with the distinction or fails to apply it properly, and that if they did they too would be in the pickle philosophers are, unable to bridge the gap. Most people just don't notice, or don't understand what a big deal this is, that's the mantra of philosophy. (The other example that leaps to mind also comes from Hume: how do you know the sun will rise tomorrow?) — Srap Tasmaner
Speak for yourself. :smirk:Philosophers: Ordinary folk think too less.
Ordinary folk: Philosophers think too much.
We never hit the sweet spot betwixt deficiency & excess now do we? We're always swinging, pendulum-like, back and forth between extremes. The aurea mediocritas isn't easy to either attain or maintain. — Agent Smith
Depends on what you mean by "proposition". Propositions can be ink marks on a piece of paper, or vibrating air molecules when speaking.But a material object cannot literally be a part of a proposition and therefore cannot be part of a fact. — Art48
I don't get this distinction between everyday, ordinary usage and some other usage. Usage depends on context. Why should we consider a philosophical context any different than any other context? The idea of ordinary usage takes into account these various contexts. What is ordinary about the usage is that it is ordinary to use the terms that way in those contexts. Any unordinary usage would be a misuse of terms in that context. When we agree on new uses for a term we are essentially creating a new context with which we use the term.In everyday usage, sure. — bongo fury
Just another way of saying that it is a misuse of language.Clearly an absurd conclusion. — Andrew M
Yet you did assert that you know when you didn't with ordinary usage. You just know something different now.There isn't an epistemic difference (i.e., either way, one is correct or mistaken about whether it is raining). However there is a semantic difference. With the "knowledge changes" position you can know it is raining when it isn't, on ordinary usage you can't. — Andrew M
As I already pointed out, you being mistaken is good evidence that you can still be mistaken with any knowledge claim, which is to say that you can never know that you know. So thinking of knowledge as a changing interpretation based on new good evidence resolves the issue. There can be right and wrong interpretations. A wrong interpretation is not no interpretation, just a different one based on the good evidence one had at the time. Given that evidence you had at the time, it would be a valid interpretation. So either we make knowledge a synonym of interpretation or we just omit the word from usage because it would be useless. Using knowledge as a synonym for interpretation is how we use the word in ordinary usage anyway when we take into account how we used the term, "knowledge" in the past as well as now when we say we know but can't know that we know thanks to the good evidence that our interpretations have changed in the past.If you want to know whether it is raining then looking out the window provides good evidence. You can say that you know it, but be mistaken, as with any claim. You can also know that you know. That's just how the logic of the usage plays out. As mentioned, the standard for claiming knowledge isn't Cartesian certainty. So its possible to think that you know that you know when you don't. — Andrew M
Which addresses my question that I asked before about how many observations need to be made before we can claim knowledge which you responded:You could be wrong again and again. But that's unlikely for a given case, since you require good evidence for each iteration of the claim. The space of possibilities rapidly diminishes. Consider what it would take to be wrong that the Earth orbits the Sun. — Andrew M
How would you know that the space of possibilities "rapidly diminishes" without knowing how many observations need to be made? You are claiming to know something that you couldn't possibly know or else you would have made the correct interpretation in the beginning if you knew how many observations you needed to assert knowledge.But "every possible observation" is not the standard for making knowledge claims or forming beliefs. — Andrew M
Which is to say that the interpretation we had was valid given the reasons we had at the time. Our interpretation can change, but that doesn't mean that we never had an interpretation in the past.It can be a good reason at the time. It may no longer be a good reason in the light of new evidence. Also there need be no infinite regress, as suggested by the orbit example. At some level of evidence you expect to converge on the truth. — Andrew M
Which is the same as saying that it was a valid reason for arriving at that interpretation. Knowledge claims can be made if we define knowledge as an interpretation (which I have already shown that the ordinary usage of knowledge is a synonym for interpretation). So we do have interpretations/knowledge. What constitutes good reasons for one interpretation does not qualify as good reasons for a different interpretation. If you become aware of new evidence then you amend your interpretation. This doesn't disqualify that looking out the window is good evidence for interpreting that it is raining. Most of the time it is, and still is even though you were mistaken once before.It is good evidence. If it weren't, then essentially no knowledge claims could ever be made (as Descartes discovered). Yet we do have knowledge. However what constitutes good evidence at one time may no longer be sufficient in the light of new evidence. If you become aware that your brother sprayed the window, then you retract your former claim, since the fact that you looked out the window is no longer a good reason to believe it was raining (though it was a good reason before). — Andrew M
As if Wittgenstein is the prophet of propositions. :roll:Read Wittgenstein’s Philosophical Investigations. — Michael
Which is to say that we have definitions of life that allow us to distinguish it from things that are not alive. All I'm asking is what those distinctions are. If you can't even answer that simple question then it does not follow that a chicken is not a proposition. A proposition could be anything, which makes your arguments non-sensical.What is life? I know that I’m alive and that a rock isn’t. But there’s no proper understanding of what life is, with over a hundred proposed definitions. — Michael
What is a definition if not the suggested, or commonly understood way of using the term? What you're saying is that you don't know how to use the term, proposition, so it doesn't follow that you can know how they relate using formal logic.I said I can't give you a definition of "proposition", just as I can't give you a definition of "number". But I know which things are numbers, which things are propositions, and which things are neither.
And I know that 2 + 2 = 4.
And I know that modus tollens is a valid rule of inference.
And I know that chickens are animals.
That's all that matters for this discussion. — Michael
That's not necessary. You've already shown that you have no idea what you're talking about, which is the point I was trying to make. Thanks. :smile:I can't give you any meaningful definition of "proposition", just as I can't give you any meaningful definition of "number". I can give you examples of things which are either numbers or not numbers, and examples of things which are either propositions or not propositions.
But, again, this has nothing to do with Fitch's paradox. If you want to talk about what propositions are then start another discussion. — Michael
I wasn't asking for an in-depth metaphysical understanding of the nature of language. It's not necessary to answer a simple question. You said, "I don't know". I'm just asking for a simple definition of "proposition". What do you know, if anything, of what a proposition is? You have to have some understanding of the nature of numbers to do maths, or else what are you doing when you do maths?. :roll:I don't need to have some kind of in-depth metaphysical understanding of the nature of language and reasoning to make use of formal logic, just as I don't need to have some kind of in-depth metaphysical understanding of the nature of numbers to do maths. — Michael
You keep using this term, "proposition" that you've you admitted to not knowing what they are. If you don't know what propositions are, then how can you even know what kind of relationship exists between them? You just continue to post scribbles on this screen and asserting that there is a relationship between them, but don't know what the members of that relationship actually are.Formal logic is concerned with the relationship between propositions. — Michael
Which isn't any different than saying knowledge is an interpretation that changes with new evidence - not that you never had it.We don't. But "every possible observation" is not the standard for making knowledge claims or forming beliefs. Good evidence is. If good counter-evidence emerges, then we should change our minds and retract the former claim. — Andrew M
Yet we asserted that we did know and were wrong, which is good evidence that you could be wrong again, and again, and again - hence no such thing as knowledge unless we define knowledge as an interpretation that changes - not that you never had it. So, using your "good evidence" definition, you have good evidence that you can't ever possess good evidence. Your argument defeats itself.You can look out the window at the moment your trickster brother sprays the window with a hose.
— Harry Hindu
In which case you wouldn't know it was raining, you would just think you did. — Andrew M
As I pointed out, it is very possible that your good reason or evidence isn't actually a good reason or evidence, and you only find that out after you get good reason or evidence, yet it is very possible that your good reason or evidence isn't actually good reason or evidence, and you only find that out...,etc. It's an infinite regress.Is it possible to believe a truth? How would that be different than to know a truth?
— Harry Hindu
Yes. To know it also requires good reason, or evidence, or justification. — Andrew M
No. It is you that assumes a standard of infallibility or Cartesian certainty by saying that "good evidence" is what is needed to possess knowledge. I'm simply asking you to define what that means, if not that "good evidence" is a state of infallibility (knowing the truth). I already pointed out that looking out the window is not good evidence because your brother could be spraying the window with a hose.How do we ever know that we have all the evidence necessary to assert knowledge over belief?
— Harry Hindu
Your question assumes a standard of infallibility or Cartesian certainty. But you can say that you know it is raining (or not) by simply looking out the window. That's the relevant standard for making knowledge claims. — Andrew M
This is circular.Another way to think of this is in terms of Ryle's achievement verbs. We can believe or claim that it is raining and be mistaken but we can't know that it is raining and be mistaken, since to know that it is raining is to be correct and for good reason (e.g., we looked out the window). — Andrew M
But this misses the point that what we used to call knowledge wasn't knowledge in light of new observations, but observations is what allowed us to assert knowledge that we didn't have in the first place. So how do we know that we've made every possible observation to assert we possess knowledge? Seems to me that either knowledge is not related to truth as Michael's non-omniscient principle seems to state:Indeed, and that's the point. When we discover that a former knowledge claim was mistaken, we retroactively downgrade its status from knowledge to belief. We say that they didn't know it after all, since we no longer believe that it was true then. — Andrew M
or "knowledge" is a useless term and we can only ever believe our assertions.some truths are unknowable — Luke
But A does not say either way. B tries to clarify the distinction but fails whenIn practice it may be that asserting a proposition implies that one believes one's assertion (see Moore's paradox), but in formal logic there is a distinction between asserting that a proposition is true and asserting that a proposition is known to be true. — Michael
It seems to state that knowledge and truth are not related.The non-omniscience principle states — Michael
You don't understand the question, what is knowledge?I don't understand what your comments have to do with anything. — Michael
But one has reasons to believe alien life exists and that it will rain tomorrow. What reasons does one have to know that know one knows alien life exists or that it will rain tomorrow?I might believe it to be so? e.g. alien life exists, the real part of every nontrivial zero of the Riemann zeta function is 1/2, it will rain tomorrow. — Michael
It seems to me that b renders a as a meaningless string if scribbles.a the cat is on the mat
b nobody knows that the cat is on the mat
Both a and b are true. This means that, even though a doesn't say so about itself, a is an unknown truth. — Michael
I think most of it hasn't been to discuss whether or not an external material world exists, but what everyone means by, "external", "material" and "world". Threads like this tend to go on forever because we are all talking past each other and misusing terms. Some are artfully (not literally) using terms in playing word games and don't seem to have the intention of saying much of anything useful.I am posting this on page 33 of the topic "Is there an external material world?", which is very close to 1000 responses!
I really wonder and cannot believe how could such a trivial and without real value or use --for me, of course-- question, the answer to which is more than obvious,, could arise such a huge interest and create such a huge discussion! — Alkis Piskas
Probably because it would be useless to its survival. Would it be useful to know that there are two birds looking to eat it for lunch? Perceiving more than one bird but less than 3 birds would be useful to its survival.My view is that ideas already exist in the mindscape, just as trees exist in the landscape. Seeing a pair of apples may awaken our mind to the idea of two, but the idea already exists. Any being which lacks the mental capacity will never perceive the idea "two." Imagine an earthworm, for instance, crawls over two pebbles. I doubt the idea of two ever enters what mind it has. — Art48
Don't you mean our mind plays the role of the picture on TV and the cameras and microphones at the baseball game play the role of the senses? Do we directly experience our mind? What information are we missing when experiencing something indirectly vs. directly? For instance, what information are we missing by watching the game on TV vs being at the game? We know the score and can see and hear the announcer describing the plays whether we are at the game or watching it on TV, so what is missing? If you asked me about the game the next day and I was able to tell you the score, who won and about the great plays that were made, how could you tell if I was at the game or watched it on TV?An analogy: Imagine indirect experience as watching a baseball game on TV, as opposed to being in the park. We don’t directly experience the tree; our senses play the role of TV. — Art48
How did we come to understand, or possess, the idea of "particular" and its relation with the idea, "unversal"?Apple is a universal. A particular apple is an instantiation of the universal called “apple”. — Art48
What reason does one have for "applying the idea of two to a pair" of objects, if not for communication?Without the idea of two, we cannot apply the idea of two to a pair of apples. Example, I define “xyz” as the set of all xyz things. Not a very useful definition. — Art48
Is the apple/atom left the only apple/atom in existence? If not, then there are still at least two apples/atoms that exist.Moreover, the set of all existing two things is constantly changing. If I eat one of the two apples, then the “set of all existing two things” has changed. If two atoms are crushed out of existence in some neutron star in another galaxy, the “set of all existing two things” has changed. — Art48
How do ideas and physical objects interact? How did you come to know of the concept, "physical"? What are you referring to when you use this term?Ideas exist in the “mindscape.” Physical cats exist in the physical world. — Art48
How did you come to experience the universal by observing just one pattern (a particular) of rough brown patches and smooth green patches?Experience is concrete. I physically experience rough brown patches and smooth green patches, which lead me to mentally experience a universal, i.e., the idea of a tree. — Art48
From where did we get the idea of two if not by first observing more than one thing? How can we observe more than one thing if we don't already posses the category "tree" of which many similarly looking things are are a member of? Without categories there would only be one of everything.Without the idea of two, we cannot apply the idea of two to a pair of apples. Example, I define “xyz” as the set of all xyz things. Not a very useful definition. — Art48
Objectivity is not limited to static pictures. You can describe an event objectively as well. Objectivity is simply a description of how things are and is independent of other people's agreement or disagreement with you. Are you not telling us how things are for everyone even if we don't agree with you?Here’s the difference between an objective truth claim and a postmodern assertion. The former invokes a picture of the way things are. This picture consists of a specific, arbitrary content. The postmodernist is not offering a picture containing an arbitrary content. They argue that we are constant moving from one picture, one value content to another. It is not the particular claims, schemes, worldviews , objective definitions that the postmodernist is interested in describing , but the movement. And saying that they are ‘describing’ something is not quite accurate, as if they stood outside of this flow. Rather, the postmodernist is enacting change and movement in talking about it. Their assertions are self-reflexive, already caught up in and changed by the flow. — Joshs
Not when you're arguing against certain brands of anti-realism which deny the "trivial" distinction that realists take for granted. — Michael
Then your posts are objective because your posts are fixed descriptions about sone aspect of nature or reality, like the relations between writers, readers, words and what they represent.Intersubjectivity is different than objectivity. The former is a dynamic pattern of interconnective relationality that cannot be captured by a formula or rule capturing the whole. The latter looks for a rule, law , fixed description applying to some aspect of nature. Objectivity tries to ground fluid self-organization on some content external to it which is not fluid — Joshs
In this instance "not part" means not in the U.S. which is a spatial relationship and "seperate" in this sense is the literal sense. I already pointed out words are not special in this regard.Well, I have a map of the United States which is definitely not a part of the United States. — Michael
This doesn't address what I said. If you dont mean "separate" in the same way you mean "not part", then what do you mean? If you don't literally mean what you say, then what do you mean literally? The relationship between the scribbles and the cat and the mat is one of representation, not seperate. If you want to say that the scribbles are not the cat on the mat, that is trivial and useless to the conversation. Representation is what joins the scribbles and the cat and the mat, not separates them.Exactly what I said before; the utterance "the cat is on the mat" is separate to the cat being on the mat. — Michael
As I pointed out before, the map is part of the territory, not separate. If the ones that are using the term, "separate" don't mean it literally, then they don't really mean that language is separate from the world, then what is it they do mean? Why use the term, "separate" if that isn't what they mean? Seems to me that there would be a different term that they could use - like what they actually do mean, if not separate.And again, you're just being too literal in your reading. When others talk about a distinction between language and the world understand it as your oft-quoted distinction between a map and the territory. — Michael
And neither is a table on the rug the cat being on the mat. Words are not cats. Cats are not dogs. Mats are not tables. Saying a cat is not a word is no different than saying a cat is not a mat. Words, mats, cats, tables and dogs all exist in the world and are distinguished visually and audibly. There is nothing special about words in this regard that would make one think that they are separate from the world.I think you're being too literal in your reading. They're just saying that the utterance "the cat is on the mat" is not the cat being on the mat. — Michael
Is a dinosaur a word or a type of extinct organism?I agree that how humans use language is a state of affairs, but is there an ultimate arbiter of the truth of certain statements about the world, for example about the truth of empirical propositions? Are there objective
truths about physical nature, or are these truths relative to contingent and conventional linguistic states of affairs?
Is the claim that dinosaurs existed before anybody talked about them incoherent? What if we instead say that SOMETHING existed before language-using communities named and defined them, but we can’t say that they were dinosaurs , since that is a conceptual convention? — Joshs
If boundaries are arbitrary then the boundary between fact and convention is arbitrary. The boundary between letters, words, and sentences on this screen are arbitrary.But let us take a look at this so-called natural kind. Natural kinds, when we examine them, almost always turn out to have boundaries which are to some degree arbitrary, even if the degree of arbitrariness is much less than in the case of a completely conventional kind
like “constellation”. — Joshs
You're focusing too much on the boundaries as if they are more important than what is within those boundaries. Does the fact that the boundaries are blurry mean that everything else that isn't at the boundaries are arbitrary? There are many objects that fit neatly into the category, "star", while there are a few that lie on the boundary of that category because they share some visual characteristics with stars and also share some visual characteristics with planets. Not every object that we call, "star" lies on the boundary. When we talk about "stars" we are not talking about what is on the boundary, but what lies easily within it. The fact that similarities exist and that some objects share more similarities than differences with other objects is not something humans created. It is what allows us to categorize and use words as representations in the first place. If everything had an equal number of similarities and differences in relation to everything else then I could see language, and categories in general, being much less useful than they are now.Stars are clouds of glowing gas,glowing because of thermonuclear reactions which are caused by the gravitational field of the star itself, but not every cloud of glowing gas is considered a star; some such clouds fall into other astronomical categories, and some stars do not glow at all. Is it not we who group together all these different objects into a single category “star” with our inclusions and exclusions? It is true that we did not make the stars as a carpenter makes a table, but didn't we, after all, make them stars? — Joshs
There's a difference between making the stars and making the scribble that refers to stars as a means of communicating. Is a star a word or scribble or utterance, or is a star a thermonuclear globe of hydrogen and helium gas?Now Goodman makes a daring extrapolation. He proposes that in the sense illustrated by these examples, the sense in which we “make” certain things the Big Dipper and make certain things stars, there is nothing that we did not make to be what it is. (Theologically, one might say that Goodman makes man the Creator.) If, for example, you say that we didn't make the elementary particles, Goodman can point to the present situation in
quantum mechanics and ask whether you really want to view elementary particles as a mind-independent reality. It is clear that if we try to beat Goodman at his own game, by trying to name some “mind-independent stuff”, we shall be in deep trouble.” — Joshs
It's the other way around. Every negation holds within it its own assertion. You have to know the truth to lie. You don't need to know how to lie to tell the truth. We often give unconscious signals to others about our mental state but it takes conscious effort to lie. Telling the truth (unconsciously) is prior to the act of deceiving.Language is about the world, and I would include mathematical and visual representation in that characterization. So, it is via language that a kind of separation appears between the world and what is about it. Of course from one perspective that which is about the world is within the world, but from another perspective the world appears only within that which is about the world. Remember the nature of the dialectic; every idea holds within it its own negation. — Janus
No. I was explaining the implications of Banno's belief about the nature of truth. If "there are truths that are independent of our attitude towards them" then truth is not a meeting of the world and language, rather truth is "simply what is the case in the world" independent of what we articulate (how we use language).. Truth would simply be what is the case and what is the case is independent of our having articulated what is or isn't the case.
— Harry Hindu
And is this your belief about the nature of truth? — Joshs
I don't like putting myself in a camp designated by some philosopher's name. So I probably don't fall neatly into any camp. I want to know what you mean by "fact" and "convention". Is a convention a fact, or a state of affairs, or what is the case? How humans use scribbles and utterances are themselves a state of affairs, or what is the case.Do you agree with Hilary Putnam that “while there is an aspect of
conventionality and an aspect of fact in everything we say that is true, we fall into hopeless philosophical error if we commit a "fallacy of division" and conclude that there must be a part of the truth that is the "conventional part" and a part that is the "factual part””, and that "this dichotomy between what the world is like independent of any local perspective and what is projected by us seems to me utterly indefensible."?
Or do you prefer David Lewis , Donald Davidson or San Dennett’s attempts to hold on some form of separation between fact and convention? — Joshs
What does it even mean to "directly" or "indirectly" experience something?Let’s begin with perception. I experience the physical world though my five senses: sight, taste, touch, hearing, and smell. I do not possess a special “tree-sensing” sense. So how can I experience a tree? The answer is I do not directly experience the tree. — Art48
An abstract object is defined as something which is neither spatial nor temporal: an abstract object does not exist in space and time. (“Object” should not be taken too literally; think “abstract entity.”) A typical example of abstract objects is numbers. Numbers such as 2 or π do not exist in space/time. Yes, two apples exist in a particular place at a particular time; but the number 2 itself does not. — Art48
Then the two particular apples are also universals?We can directly see on only one thing: light. The mind does the rest. Almost everything we experience though our senses are universals, are abstract objects, are ideas in our mind. — Art48
How did you come to know the number 2 if not by seeing the scribble, "2" and seeing two of something, like seeing two apples? Are the scribbles on this screen directly or indirectly experienced?My mind directly experiences the number two because the number two is a thought and my mind experiences thoughts directly. Similarly, my mind can directly experience the abstract object named “tree” because that, too, is a thought. As to what is causing my experiences, I suppose there’s a material object, a material tree, existing in a physical universe outside myself. If I’m not dreaming, hallucinating, or a brain in a vat, then my supposition may be correct. There may actually be a material tree, existing in a physical universe outside myself. But, then again, there might not. — Art48