Comments

  • SEP reading on possibility and actuality
    How can you say that the past is fixed, when what I remember as past is changing all the time?Metaphysician Undercover

    It cannot be the case that in December 2025 “Caesar crossed the Rubicon” and in December 2026 “Caesar did not cross the Rubicon".
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    A "judgement" as your example of something which occurs "in the present", takes a lot longer than Plank time. The average human reaction time is 25 one hundredths (,25) of a second.Metaphysician Undercover

    0.25 seconds is a period of time. Similarly, one week is a period of time and one decade is a period of time.

    To call 0.25 seconds a present moment in time would be like calling a decade a present moment in time.
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    The issue is that you cannot believe that the Eiffel Tower is in Paris, and also believe that it is possibly in Reno, without implied contradictionMetaphysician Undercover

    I can believe one thing and imagine another thing.

    Believing is not the same as imagining.
  • SEP reading on possibility and actuality
    Premise that only the present exists
    My premise is that the world only exists in the present. It may be there is a minimum duration of time, such as Planck's time, It may be that even though clocks show a different time when either near a mass or accelerating, and even though the “present” may be different for each clock, it remains a fact that for each clock there is only one present. In this present we can remember the past but not the future.

    Free will vs determinism
    This is why we ought not extend the fixedness of the past into the present. Doing this produces a determinist perspective ("perspective" being present), and obscures the truly dynamic nature of the present..........................
    If we consider the present to always be a duration of time, we ought to allow that not only does part of the present share the properties of the past (fixed), but we need to allow that part shares the properties of the future (not fixed). This is necessary to allow that a freely willed act, at the present, can interfere with what would otherwise appear to be fixed.
    Metaphysician Undercover

    That we can remember the past but not the future means that for us there is an arrow of time. Between the past we remember and the future that we cannot remember is the present, the “now”.

    Both the past and present are fixed, in that we can only remember one past, and by the Law of Non-contradiction there can only be one present. Therefore, both the past and present must be static rather than dynamic.

    As regards the future, also by the Law of Non-contradiction, the future that will exist must be fixed, and thereby static rather than dynamic. As we cannot remember this future, we don’t know what this future will be. However, we do know from the laws of logic, necessary and universal, that this future will be fixed, static rather than dynamic.

    A reality that is fixed must be deterministic, meaning that free will must be over and above any deterministic fixed reality, and within a meta-reality. By its very nature, a meta-reality must be unknowable within any deterministic reality. Similarly, the meaning of a language cannot be discovered within the language itself, but can only be known in a meta-language external to the language itself. As we cannot use language to discover meaning within itself, but only through a meta-language, we cannot use a deterministic reality to discover free will within itself, but only through a meta-reality.

    Whether one believes in a meta-reality enabling free-will in our reality is a matter of faith rather than logic.

    Memories
    The reason i am making this distinction is because we experience the present as active, and changing, so we ought not think of it as "fixed".................
    "The present" is very difficult because things are always changing, even as we speak. ……………….
    Then the statement “there is a truck coming round the corner” is judged to be true, or stated as true, based on that observation which is now past.
    Metaphysician Undercover
    We experience the present and have memories of the past. If the present has a duration, then it may well be of the order of Plank’s time, but certainly not much more than that. I observe a truck coming round the corner, which quickly becomes a memory. I can then make a judgement, such that the truck was travelling too fast, but this judgement was made in the present and based on a memory of the past.

    Imagination
    If the Eiffel tower is in Reno, then it is not in Paris. If I believe that the Eiffel Tower is in Paris, then it is implied that I also believe it is impossible that it is in Reno, which is somewhere other than Paris. Therefore to believe that it is possible that it is in Reno, implicitly contradicts my belief that it is in Paris.Metaphysician Undercover
    I see an apple on the table and imagine a yoghurt in the fridge. It is not a contradiction to observe something and imagine a different thing. Similarly, I can see the Eiffel Tower in Paris and imagine the Eiffel Tower in Reno. Neither is this a contradiction.
  • SEP reading on possibility and actuality
    Here is a state of affairs: John walked from the entrance to the park to the exit. There simply is no requirement that a state of affairs must be a temporal instant. We can talk about a state of affairs at an instant or a state of affairs over time.Banno

    I have been assuming that a state of affairs is to be understood as something existing in the world rather than in the mind.

    If states of affairs exist in the mind, I can understand that in the mind there can be a state of affairs over a period of time, such as “John walked from the entrance to the park to the exit.” We do have memories of the past. I understand that we can talk about a state of affairs at an instant and over time if it is a concept in the mind. If states of affairs exist in the mind, they can be both static and dynamic.

    But how can a state of affairs exist in the world over a period of time when in the world a period of time does not exist. In the world only the present exists. In the world the past and present don’t exist at the same time. If the past and present don’t exist at the same time, there can be no existent period of time in the world. If states of affairs exist in the world, they can only be static.
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    So all the seemingly profound "Past events cannot exist in a world that only exists in the present" says is that if we only talk about the present, then we can't talk about the past.Banno

    Even though we only exist in the present, we can talk about the past because we have memories of the past.

    I have a memory of being at the entrance of the park and have another memory of being at the exit of the park. This allows me to say “I walked from the entrance of the park to the exit of the park”.
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    And the odd result of stipulating the restriction of putting all our sentences int he present tense is that a simple sentence such as "Caesar crossed the Rubicon" ceases to have a truth value... no small problem.Banno

    My memory allows me to put my sentences in the past. I remember that “I was at the entrance to the park”.

    The proposition “I was at the entrance to the park” is true because I remember that I was at the entrance to the park.

    Propositions in the past tense still have truth values because of present memories.
  • SEP reading on possibility and actuality
    We think about what we want and how to get it, without necessarily thinking about the way things are.Metaphysician Undercover

    I have the thought that there is an apple on the table.

    If I did not believe that there was not a correspondence between my mind and the way things are in the world, I would not attempt to pick the apple up.
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    You contradict yourself. If, in your mind the Eiffel Tower is in Paris, you contradict yourself to say that in your mind it is also possible that the Eiffel Tower is in Reno.Metaphysician Undercover

    It is possible to think about different states of affairs in the world.

    I can believe that the Eiffel Tower is in Paris, whilst also imagining the Eiffel Tower being in Reno. These are not contradictory thoughts.
  • SEP reading on possibility and actuality
    Allowing that counterfactuals are possibilities violates the principle of truth as correspondence in a fundamental way.Metaphysician Undercover

    Using your term “ontological possibility”. As regards the proposition “there will be a truck coming round the corner”. In the present, we cannot know whether this proposition will be true or not. However, we can know that either it will be true or won't be true. This is a future possibility

    Using your term “epistemic possibility”. As regards the proposition “there is a truck coming round the corner”. In the present, it may be that we don’t know whether this proposition is true or not. However, we can know that either it is true or is not true. This is a present possibility.

    You base your claim on counterfactuals. You say “but they are not truly "possible" in any rational way, so they need to be excluded, as not possibilities at all.” It is true that both the past and present are fixed. The present is as fixed as the past. If there is a truck coming round the corner then it is true that “there is a truck coming round the corner”

    There are two senses to the word “possible”, one used in logic and one used in ordinary language.

    In the sense of logic, if “the truck is coming round the corner” then it is not possible that “the truck is not coming round the corner”. This would break the Laws of Non-contradiction and Excluded Middle.

    In the sense of ordinary language, if “the truck is coming round the corner” then it is possible that “the truck is not coming round the corner”. In ordinary language we use possibility all the time. It depends on whether present facts are necessary or contingent. It is certainly not the case that it is a necessary fact that “the truck is coming round the corner”, as the driver could have over-slept, been caught in a traffic jam, had a flat tyre, etc.

    It may be argued that counterfactuals which violate the laws of nature, such as “the truck was travelling faster than the speed of light” must be necessary and therefore not possible, whilst counterfactuals which don’t violate the laws of nature, such as “the truck is not coming round the corner” are contingent and therefore possible.

    Counterfactuals don’t necessarily violate the principles of truth if they are contingent rather than necessary.
  • SEP reading on possibility and actuality
    If we have a true (by correspondence) world, the other proposals which contradict are false, and they cannot be considered as possibilities.Metaphysician Undercover

    That my thoughts do correspond with my actual world is the very basis for enabling me to think about other possibilities.

    In my mind is the thought that the Eiffel Tower is in Paris. In my actual world the Eiffel Tower is in Paris.

    There is a correspondence between the thought in my mind that the Eiffel Tower is in Paris and the fact that in my actual world the Eiffel Tower is in Paris

    In my mind is the thought that it is possible that the Eiffel Tower could be in Reno. In a possible world the Eiffel Tower is in Reno.

    There is a correspondence between the thought in my mind that it is possible that the Eiffel Tower is in Reno and a possible world where the Eiffel Tower is in Reno

    That there is a correspondence between my mind and my actual world does not nullify any correspondence between my mind and a possible world.

    That my thoughts do correspond to my actual world (I think that the Eiffel Tower is in Paris and in fact it is in Paris), is the very basis for enabling me to think about other possibilities (I think that the Eiffel Tower could be in Reno).
  • SEP reading on possibility and actuality
    But the state of affairs that snow is white doesn't sound right.Ludwig V

    In Wikipedia State of affairs (philosophy)
    For example, the state of affairs that Socrates is wise is constituted by the particular "Socrates" and the property "wise".

    I have been assuming that a State of Affairs is something like “Socrates is wise”

    I cannot see a reference to States of Affairs In SEP Possible Worlds 1.1. Do you mean 2.2.1. But 2.2.1 is part of 2.2 Abstractionism.
  • SEP reading on possibility and actuality
    Further, there is more to states of affairs than objects and properties. The drop back to the intensional, Aristotelian notion of properties and objects is retrograde. Substance-property ontology is far too simplistic. Much better to continue to use extensionality.Banno

    As I see it so far:

    Truth by T-sentence
    “Caesar crossed the Rubicon” is true IFF Caesar crossed the Rubicon. But this does not tell us whether Caesar crossed the Rubicon or not

    Extensional truths
    Suppose there are two sets
    Set 1 = {not Caesar, Mario, Francesco}
    Set 2 = {Caesar, Mario, Francesco}

    Suppose there is the proposition “a person crossed the Rubicon”.

    We don’t know which set is the domain of the proposition.

    But if we did know that set 2 is the domain of the proposition, then “Caesar crossed the Rubicon” is true because Caesar is within the domain {Caesar, Mario, Francesco}. This is an extensional truth. But in this case, this extensional truth is analytic, as we included Caesar because we know it is true that he did cross the Rubicon.

    Intensional truths
    Given the proposition “Caesar crossed the Rubicon”, this is either true or not true, but it may be that we never know.

    Necessary a posteriori truths
    We could have a necessary a posteriori truth. It is necessarily true that either Caesar either did or did not cross the Rubicon (assuming Caesar existed). We may not know the truth today, but we may know the truth in the future. Then “Caesar crossed the Rubicon” will be a necessary a posteriori truth.

    Necessary contemporaneous truths in the mind
    The only real truths are necessarily contemporaneous in the mind.

    I see a red postbox and it is true that I see a red postbox. But the fact that I see a red postbox does not mean that it is true that in the world is a red postbox. In the world may be a green bollard.
  • SEP reading on possibility and actuality
    Actions are usually differentiated from events, such that an action requires an actor and is intended by that actor.Banno

    Properties - actions - events

    Property = the characteristic of a being, such as “John is a walker”

    Action = something done by a sentient being, such as “John is walking”

    Event = something that is done to either a sentient or insentient being, such as “John is winning” or “snow is falling”.

    States of Affairs (SOA)

    A SOA is the way the world is.

    Some consider a SOA to be a static truth rather than a dynamic process.

    Being a static truth, the predicate will be a property, such as “John is a walker”

    The predicate cannot be an action, which is dynamic, such as “John is walking”.

    An action changes one SOA into a different SOA, such that the action “John is walking” changes one SOA, “John is at the entrance to the park” into a different SOA “John is at the exit to the park”.

    The predicate cannot be an event, which is dynamic, such as “John is winning” or “snow is falling”

    An event changes one SOA into a different SOA, such that the event “John is winning” changes one SOA, “John is poor” into a different SOA “John is rich”.

    You say that a SOA can be dynamic. It seems to me that a SOA is static. Is there any authoritative judgement?
  • SEP reading on possibility and actuality
    In section 1.1, I discovered that states of affairs are in fact expressed by gerund clausesLudwig V

    There is the SOA (snow is white)
    There is also the SOA (snow, being white, is well known)

    There is the problem of disconnecting the world from the thought of the world, when we only know the world through our thoughts.

    Being known is a thought, but then being white is also a thought.
  • SEP reading on possibility and actuality
    Possible world semantics necessitates that the propositions, states of affairs, or whatever, reference our ideas, not any independent physical world.……………This is why truth by correspondence is excluded…………………That is why I claim that possible worlds semantics is fundamentally sophistry.Metaphysician Undercover

    I would have thought that the main purpose of Possible World Semantics (PWS) is to reference the world, meaning that correspondence is a core part of PSW. The terms possibly, necessarily, ought, could, might, etc are central to understanding the meaning of ordinary language, and ordinary language is useful when it does refer to the world. “If I cross the road now, there might be a truck around the corner, and I could be knocked down” is a real world situation where modal terms are critical.

    In your own writing, an understanding of modal terms is necessary if we are possibly to understand the meaning of the paragraph.
    We should look at combinatorialism. It's a bit more complicated, but I think it may provide the best approach out of the three. The problem which jumps out at me, is the issue with substantiating the proposed "simples". This idea of simples is similar to the ancient atomists. That the concrete world could actually be composed of such simples as the fundamental elements, is shown by Aristotle to be problematic.

    I agree that some philosophers may be more interested in publishing articles than coming up with an agreed solution, but that is always the case. However, it does not take away from the day to day relevance of PSW.
  • SEP reading on possibility and actuality
    I would say leave out the word "reality."frank

    But TLP 2.063 The sum-total of reality is the world
    And 2.12 A picture is a model of reality
    If Wittgenstein is a major source for the meaning of a state of affairs, we will need to consider reality
    ===========================
    Wittgenstein (in the Tractatus) is saying that the boundaries of what we call the world are precisely the same as the boundaries of thought.frank

    Yes, TLP 5.6 The limits of my language mean the limits of my world
    But how can I know states of affairs in the world if my knowledge of the world is limited by my language. Does this infer that states of affairs only really exist in my language.
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    When we talk or think about the world, we don't usually think of it as a collection of objects, but rather as a complex of relationships and events. We'll call these complexes states of affairs. They're closely kin to propositions.frank

    But TLP 2.01 A state of affairs (a state of things) is a combination of objects (things)
  • SEP reading on possibility and actuality
    And it seems to me that in trying to make sense of both logic and mind, you mix these two.Banno

    Some thoughts:

    For Wittgenstein, States of Affairs (SOA) are the fundamental building blocks of reality in the world, and are about how objects can be arranged. The parts of these SOA’s naturally go together, such that it is in the nature of Socrates to be wise. If a SOA exists in the world then it is a fact.

    Using brackets to try to make things clearer. IE, “snow is white” is true IFF (snow is white).

    There are two aspects

    Aspect one - a State of Affairs is not an object’s action

    A State of Affairs is the relation between an object and a property, such as (snow is white).
    An action is not a property. Therefore, (snow is melting) cannot be a State of Affairs.
    As crossing the Rubicon is an action, (Caesar crossing the Rubicon) cannot be a State of Affairs.

    Aspect two - a State of Affairs is an object’s property

    Situation one, an existent object in the present
    Consider the proposition “Sir James Hockenhull is a General”

    “Sir James Hockenhull is a General” is true IFF (Sir James Hockenhull is a General).

    This is true, as (Sir James Hockenhull is a General) is a State of Affairs that obtains..

    Situation two, a non-existant object in the present
    Consider the proposition “Caesar is a General”.

    This can be neither true nor false, as Caesar does not exist in the present. Therefore, (Caesar is a General) cannot be a State of Affairs.

    Situation three, a non-existant object in the past
    Consider the proposition “Unicorns were white”

    This can be neither true nor false, as Unicorns do not exist either in the present or past. Therefore, (Unicorns were whitel) cannot be a State of Affairs.

    Situation four, an existent object in the past
    Consider the proposition “Caesar was a General”.

    1 - On the one hand
    States of Affairs exist in a mind-independent world.
    The world only exists in the present.
    Past events cannot exist in a world that only exists in the present
    Therefore the past event (Caesar was a General) cannot exist in a world that only exists in the present.

    Therefore, (Caesar was a General) cannot be a State of Affairs

    2 - On the other hand
    We may have the concept of a possible world where there is the State of Affairs (snow is white), and we may also have the concept of a possible world where there is the State of Affairs (snow is black).

    If we can have the concept of a possible world where there is the State of Affairs (snow is black), it seems to follow that we could also have the concept of a possible world where there is a State of Affairs (Caesar was a General).

    The problem

    As you say, “There is a big difference between "The apple is on the table" and "Russell thinks there is an apple on the table". And it seems to me that in trying to make sense of both logic and mind, you mix these two.”

    We can only know about a State of Affairs in a mind-independent world through concepts in the mind, yet we are trying to determine States of Affairs independently of the mind

    Ultimately, States of Affairs cannot be about what exists in a mind-independent world, but must be about our concepts of what exists in a mind-independent world .

    If that is the case, then the enquiry is not about the State of Affairs in the world (Caesar was a General) but more about the State of Affairs in the mind “Caesar was a General”.
  • SEP reading on possibility and actuality
    Quantification is not reference. So “there is no apple on the table” is ~∃x(Ax ^ Tx). But "There is no apple in the set” is ambiguous between ~∃x(Ax ^ Tx) and ∃(x)(~A(x) ^ T(x)) This last asserts that there are no apples at all. it's as if we read "There is no apple in the set” as saying that there is a non-existent apple on the table.Banno

    I am slowly working through your posts.

    Yes, the word “obtain” is redundant in possible worlds, although still relevant in First Order Logic.

    Yes, we cannot list all possible positions between two points, as such a list would be infinite.

    What makes an apple the same apple in different possible worlds?
    Russell’s Theory of Descriptions may have a flaw that truth is not always the property of a sentence. Kripke’s Rigid Designator may have the flaw in that names can still be used non-rigidly. Gareth Evans in his own theory of names attempts to combine a theory of descriptions with rigid designation.

    As regards Plantinga
    I can understand that in a possible world there may or may not be an apple. I can understand that if there is an apple, then this apple has its own unique haecceity. But I cannot understand that if in a possible world there is no apple, there still is the apple’s haecceity (though I listened on YouTube to a talk he gave at New York University about Naturalism and Evolution, and his arguments seemed quite weak)

    As regards states of affairs being dynamic.
    An apple falls off a branch and hits the ground. We cannot describe the movement of the apple from tree to ground by listing each position it will be in, as this list would be infinitely long, but we can describe its position knowing it is falling under a gravitational force of 9.8 m/s sq

    What exactly is a state of affairs.

    SEP - States of affairs
    According to Wittgenstein’s Tractatus Logico-Philosophicus, the totality of states of affairs exhausts the space of possibilities; the totality of states of affairs that obtain are the (actual) world.

    Wikipedia - State of Affairs (philosophy)
    In philosophy, a state of affairs (German: Sachverhalt),[1] also known as a situation, is a way the actual world must be in order to make some given proposition about the actual world true; in other words, a state of affairs is a truth-maker, whereas a proposition is a truth-bearer

    This suggests that a state of affairs is part of the actual world.

    But the actual world can only exist at one moment in time. There is one moment in time when the apple leaves the tree, there is one moment in time when the apple hits the ground, and many moments in time between the two. At each moment in time, the apple will be at one position.

    Even so, it may be that this moment in time has a duration, such as Planck time, and a position in space has an extension, such as Planck length.

    Even if time has a minimum duration and space has a minimum extension, if a State of Affairs does exist in the actual world, then it can only exist as something within a moment in time, meaning that it is static rather than dynamic.

    The equation s = 0.5 f t sq, which describes a change in position with a change in time, cannot exist as a State of Affairs in the actual world, as a State of Affairs can only exist in one moment in time, and a change in time cannot exist within one moment in time.

    If a State of Affairs is something that is part of the actual world, because in the actual world time can only exist as a series of moments, a State of Affairs can only be something static.

    What are the implications that existence is not a predicate
    In a possible world, there may or may not be an apple.

    If there is a single apple in this possible world, it would be redundant to say that “the apple exists in this possible world”, as this would be equivalent to saying “an existent apple exists in this possible world”. It would be better to say “there is an apple in this possible world”.

    In there are no apples in this possible world, it would be redundant to say that “the apple does not exist in this possible world”, as this would be equivalent to saying “a non-existent apple does not exist in this possible world”. It would be better to say “there is no apple in this possible world”.

    If existence is not a predicate, then neither can non-existence be a predicate

    Similarly with the mind. I may or may not have the concept of an apple.

    If I have the concept of an apple in my mind, it would be redundant to say that “the concept of an apple exists in my mind”, as this would be equivalent to saying “an existent concept of an apple exists in my mind”. It would be better to say “there is the concept of an apple in my mind”.

    If I don’t have the concept of an apple in my mind, it would be impossible to say that “the concept of an apple does not exist in my mind”, as it would be impossible to say “a non-existent concept of an apple does not exist in my mind”. One cannot say anything.

    Even though there is no apple in my actual world, I can still have the concept of an apple in my mind. Then when I refer to an apple, I am not referring to something in the world but am referring to something in my mind.
  • SEP reading on possibility and actuality
    What we need is a way of seeing through the problems so that we can understand that they are illusions created by our misunderstanding of language. That's what the logical analysis is intended to do.Ludwig V

    :up:
  • SEP reading on possibility and actuality
    Semantics do not imbue existence.Relativist

    A book could be written on that topic.

    Linguistic determinism regards language as determining how people perceive existence.

    Plantinga, being a Christain philosopher, may argue that "In the beginning was the Word", and from the word came existence. Benjamin Lee Whorf proposed that language does not merely describe objects, but rather determines what we perceive an object to be. Wittgenstein argued that the limits of our language define the limits of our world. Plato considered that conceptions of reality are embedded in language. For the Indirect Realist, objects such as a red postbox only exist as the name “the red postbox”.

    We can talk about Sherlock Holmes who does not exist, and Meinong’s logic can deal with non-existent objects, such as round-squares
  • SEP reading on possibility and actuality
    Strictly speaking, we do not "observe" time at all. If a person sees an apple moving one can deduce that time has passed, but we do not observe time. So "time" itself is a mental construct.Metaphysician Undercover

    I agree that on the macro scale, such as an hour, we cannot observe time, because we exist within time. Only a being outside of time could observe time. As you say, time is a mental construct that we deduce. For example, from our memories.
    ==========================================
    So, what I would say is that we are always experiencing and observing a duration of time.Metaphysician Undercover

    I agree that on the micro scale, such as a second, I do feel that I experience a duration of time, even though intellectually I believe that there can be only one moment in time. Very mysterious.
  • SEP reading on possibility and actuality
    The representation of the present as a "moment in time" is completely inconsistent with empirical observation, therefore a falsity.Metaphysician Undercover

    When I see an apple falling to the ground, are you saying we are able to empirically observe more than one moment in time at the same time?

    This would mean that we are able to empirically observe the moment in time when the apple left the tree and at the same time also empirically observe the moment in time when the apple hits the ground.

    It is more the case that when we empirically observe the apple hitting the ground, we have a memory of the apple leaving the tree.
  • SEP reading on possibility and actuality
    But ¬∃x(P(x)∧Q(x)) identifies a different state of affairs, which does not refer to any apples.Ludwig V

    Learning about logic statements.

    ¬∃x(P(x)∧Q(x)) is the situation that there is not something that that is both an apple and on the table

    ∃x(P(x)∧¬Q(x)) is the situation that there is at least one thing that is an apple and not on the table

    In possible world, say W34, there are no apples at all. Then the proposition “there is no apple on the table” is true.

    What would the logic statement be for this possible world W34?
  • SEP reading on possibility and actuality
    I suggest that it's simpler to semantically equate, “there is no apple on the table” with the fact that apples are not in the set of objects on the table.Relativist

    In ordinary language we can say “there is no apple on the table”.

    We could also list the set of things on the table = {book, pen, cup}, and then say “there is no apple in the set”.

    To say “there is no apple on the table” is no different to saying “there is no apple in the set”.

    In both cases we are referring to something that does not exist.
  • SEP reading on possibility and actuality
    Do you mean that the apple that might be on the table does not exist?Ludwig V

    As I understand it:

    In ordinary language we can say “there is no apple on the table”, so we seem to be referring to an apple that does not exist, which is a puzzle.

    But we must be referring to something.

    In logic, this problem is avoided by treating the apple as existing regardless of whether it obtains or not

    The proposition "There is something that is an apple and this something is not on the table" can be written as ∃x(P(x)∧¬Q(x)) where P(x) means "x is an apple" and Q(x) means "x is on the table"

    We can then refer to an apple that exists regardless of whether or not it is on the table.
  • SEP reading on possibility and actuality
    There is no "actual moment in time". Time is continuous duration, or flow, without any moments.Metaphysician Undercover

    Your only direct and immediate knowledge of time is that of the present, the present moment in time. Within your present, you have memories of the past. You can theorise, hypothesise, that time is a continuous duration, but you have no direct or immediate knowledge that this is the case.
  • SEP reading on possibility and actuality
    3 and 6 appear to be identicalLudwig V

    True, in ordinary language
    Possibility 1 - the apple is on the table
    Possibility 2 - the apple is not on the table
    =====================================================
    "There is no apple on the table" which doesn't refer to anything non-existent and "There is an apple on the table", which refers to the apple on the table, which does exist.Ludwig V

    In ordinary language, if “there is no apple on the table” is true, then there is no apple. The proposition is referring to something that is non-existent. This seems like a puzzle.

    As you say “I don't see how one can say anything at all about non-existent objects. They have to exist in some sense if we are to talk about them at all.”

    This is the problem that modal logic solves. The apple exists even if it does not obtain. If it exists then it can be included within modal equations.
    ==================================================
    But whether the apple in W3 is the same apple as the apple in W6 or the apple in W9 is the same as the apple in W12, - or perhaps the same apple is in question in all four worlds - is a question of trans-world identity. That's an awkward questionLudwig V

    Yes, in modal logic, if in W3 the apple exists but does not obtain, and in W6 the apple exists but does not obtain, is this the same apple or a different apple even though it is identical.

    Plantinga suggests that the apples in W3 and W6 are different even though they may otherwise be identical. This is why he attaches a haecceity to each entity that exists.

    This makes sense, in that how can two entities that exist but not obtain be the same thing.

    In ordinary language, if x does not exist and y does not exist, how can there ever be the possibility of x and y being the same thing. This is why it becomes a problem for logic to solve.
  • SEP reading on possibility and actuality
    A state of affairs isn't perspectival. The expression of a proposition will generally have the hallmarks of a certain POV, but a state of affairs is not an expression. A state of affairs that obtains is a fact.frank

    As I see it:

    Suppose in the world are the States of Affairs i) the apple is on the table ii) the apple is not on the table. These States of Affairs are not perspectival.

    If the State of Affairs, the apple is on the table, obtains, then it is a fact. This is also not perspectival.

    A State of Affairs exists even if it does not obtain.

    A State of Affairs expresses a possible world.

    When I say “the apple is not on the table”, this is perspectival from my point of view.

    Then my proposition “the apple is not on the table” is false because the apple is on the table.
  • SEP reading on possibility and actuality
    So far as I can see, "haecceity" has no meaning beyond "the property that accounts for the uniqueness of entities". It is just a label for the problem. Since non-existent objects don't exist, they can't possess haeccity". So it is doesn't help with non-existent objects. .Ludwig V

    I agree that haecceity is just a label for the problem. Though haecceity might be something other than a property.

    In Ordinary language, when we say “there is no apple on the table”, we mean that the apple does not exist.

    However in modal logic, the apple exists even though it does not obtain.

    This makes logical sense, because the apple must exist in some sense if we are able to refer to it.

    Yes, non-existent objects cannot have haecceity.

    However, non-obtaining objects can exist, and it is these that have haecceity.

    For Plantinga, even though there is no apple on the table, this apple can have haecceity.
  • SEP reading on possibility and actuality
    Why shouldn't. state of affairs list the positions some object occupies over time? As, 'The ball rolled east at 2m/s'?Banno

    It could. A State of Affairs could list the position of an object through time, such as on an Excel spreadsheet. But we look at this spreadsheet in our present moment in time. We don't need to travel through time in order to understand that the object had different positions through time.

    Similarly with the proposition “the ball rolled east at 2 m/s”. We look at this proposition in our present moment in time. Again, we don't need to travel through time to understand that the object had different positions through time.

    We only exist at the present moment in time, and have memories about the past.
  • SEP reading on possibility and actuality
    That is not consistent with empirical observations. We see activities, things moving.Metaphysician Undercover

    I am not saying that time does not exist, but even if time does exist, there is only one actual moment in time.

    Suppose a train enters a station at t1 and leaves the station at t2.

    What does “we see things moving” mean?

    At t2 we see the train leaving the station and at t2 we have the memory of the train entering the station at t1.

    It cannot mean that at t2 we see the train leaving the station and then nip back in time to see the train entering the station at t1. Time travel is not possible.

    It means that at t2 we see the train leaving the station and at t2 we have the memory of the train entering the station at t1.
  • SEP reading on possibility and actuality
    The glaring problem I see with abstractionism is that the entirety of the observed, empirical world, cannot be captured by "states of affairs". This is due to the reality of change, activity, and motion.Metaphysician Undercover

    However, the world only exists at one moment in time, which is the present. The world cannot exist at two moments in time. Even our memories of the past exist in this present moment in time.

    I agree that a State of Affairs can only capture one moment in time, but as the world can only exist at one moment in time, a State of Affairs is able to describe the world.
    ===============================================================
    As such, "possibility" cannot be understood through the application of states of affairs.Metaphysician Undercover

    The world can only exist at one moment in time. At this present moment in time, the object does not have property X, and we have the memory that in the past the object had the property X. However, this memory of the past also exists in the present.

    The Law of Contradiction would be violated if an object has the property X and does not have the property X at the same time. However, this is not the case. There is only one moment in time, and that is the present. In this present, the object does not have the property X.

    The Law of Excluded Middle has not been violated, as the proposition “the object as it is in the present does not have the property X” is true.

    At this present moment in time is my thought that it is possible that the apple is on the table. Possibility exists in this present moment in time, in the present State of Affairs. Possibility can be understood within the State of Affairs that presently obtains.
  • SEP reading on possibility and actuality
    There is no guarantee that the same bundle will not occur again. But it is no help to posit yet another property and attributing to that property the magical capacity to be uniquely found in that object. It just makes another puzzle.Ludwig V

    Perhaps this is the case:

    Ordinary language
    In ordinary language, “it is possible that the apple is on the table”.

    Possibility 3 - the apple is not on the table
    Possibility 6 - the apple is not on the table
    Possibility 9 - the apple is on the table
    Possibility 12 - the apple is on the table

    In 3 and 6, we are referring to something that does not exist as if it existed, which is a puzzle.

    Therefore, the apple referred to in 3 cannot be the same thing as the apple referred to in 6, as non-existent things cannot be identical to each other.

    Modal logic
    (23) ◇∃xTx is true if there is an accessible world in which ∃xTx

    Possible world W3 = ¬ ∃xTx
    Possible world W6 = ¬ ∃xTx
    Possible world W9 = ∃xTx
    Possible world W12 = ∃xTx

    In modal logic, rather than as in ordinary language referring to something that does not exist as if it existed, we can say x exists even if x does not obtain.

    As with ordinary language, the x in W3 cannot be the same thing as the x in W6, as non-obtaining things cannot be identical to each other. Therefore, they must be uniquely different.

    Plantanga proposed “haecceity” to account for this uniqueness of entities.
  • SEP reading on possibility and actuality
    So in a world where the apple does not exist, the haecceity "being that apple" exists, and is unexemplified.Banno

    To my present understanding:

    If I say “the apple might be on the table”, then there is a possible world where the apple is on the table.

    Following (23) ◇∃xTx is true if there is an accessible world in which ∃xTx, it is possible that for some apple, the apple is on the table is true if there is an accessible world in which for some apple, the apple is on the table.

    As you say, we need to specify what kind of worlds we are talking about, and may decide to limit possible worlds to those worlds that have the same natural laws as ours. The SOA, the apple is on the table, may exist even though it does not obtain. One advantage of the Trace Actualists is that a State of Affairs (SOA) may exist even though it does not obtain.

    Here, “exist” is being used in a particular way. This has a different meaning to ordinary language, where exists means obtains.

    For Wittgenstein in The Tractatus, if a SOA obtains then it is a fact in our actual world. Then it is a fact that the apple is on the table.

    However, if in our actual world the proposition “the apple is on the table” is false because there is no apple on the table, the proposition “the apple might be on the table” is true because there might be an apple on the table, prescribing accessible worlds as having the same laws of nature as ours.

    Therefore, in order to accommodate modal semantics, even though the SOA the apple is on the table does not obtain, the possibility of there being an apple on the table requires some kind of existence.

    The New Actualists solution is that the apple exists in a concrete sense. Even if not necessarily concrete in an actual world, contingently concrete in a possible world.

    The Haecceitists' solution, as for Plantinga, the apple exists in its haecceity, both in the actual world and all possible worlds. This haecceity is not Platonic Realism, where the property of appleness exists even if never instantiated by an apple. This haecceity is not that of mental abstract concepts independent of any physical manifestation.

    Heicceity is an historic term, going back to John Duns Scotus in the 13th C, who proposed that although an object is no more than its set of properties, haecceity makes the object unique and different to any other object.

    The idea was continued by Leibniz in his Principle of the Identity of Indiscernables, where even though two objects sharing the same properties must be identical, they remain unique and different to all other objects because of their haecceity.

    For Plantinga, every entity exists and has a unique haecceity, a primitive “thisness” that cannot be reduced to anything else, and has this haecceity even in those worlds where the entity does not obtain.

    Then how to explain Plantinga’s haecceity as something that exists in a mind-independent world, especially as he is neither proposing Platonic Realism nor suggesting that haecceity exists as a mental concept.

    How can the haecceity of an apple exist in the world even though no apples exist in the world?

    Perhaps the answer to this may be given by those who believe that numbers are discovered and not invented. I personally believe that numbers are invented in the mind. However, there are those who believe that numbers are discovered in the world, such that the number 9 exists in the world even though never instantiated in the world. In this sense, numbers may also have an haecceity.

    If there were, problems would arise. Suppose an haecceity of Theseus’s ship existed in the world even though Theseus’s ship did not obtain in the world. We know that parts of Theseus’s ship can be removed. Then for every possible configuration of Theseus’s ship there world be a different haecceity in the world, becoming infinite in number.

    Even if Platonic Realism is dismissed, haecceity as a mental concept can be understood, but Plantinga is suggesting the haecceity of an individual exists in a mind-independent world even in the absence of that individual.

    The fact that Alvin Plantinga is a Christian philosopher, and a defender of theism, may take the nature of his haecceity into the spiritual realm and away from the material realm. But that is another story.
  • SEP reading on possibility and actuality
    Several ideas are introduced here, one being to obtain.frank

    My understanding of 2.2.3

    There are Concretists such as Lewis and Abstractionists such as Plantinga.

    For the Abstractionsists:
    There is the actual world, an actual world, a State of Affairs that exists and obtains.
    There are possible worlds, non-actual worlds, States of Affairs that exist but fail to obtain.

    Most Abstractionalists are Actualists.

    There are two types of Actualists, Trace Actualists and No-trace Actualists.

    The problem with No-trace Actualists is that they cannot explain standard modal semantics, in that it is possible that for some x, x is an Exotic. But for the No-trace Actualists, there is no x.

    There are two types of Trace Actualists, New Actualists and Haecceitists.

    Trace Actualists can explain standard modal semantics, in that things, whether objects or properties, do exist in possible worlds. It is possible that for some x, x is an Exotic (so different to an actual object that no actual object could be an Exotic)

    It is possible that on the table is an apple. There is a possible world where the apple is on the table.

    For the New Actualists, the apple necessarily exists, but is not necessarily concrete. The apple is only contingently concrete.

    For the Haecceitists, such as Plantinga, even though in a possible world the apple does not exist, the property “being an apple” does exist.

    For Trace Actualists, things in possible worlds can exist. This allows the modal semantics of (23) ◇∃xEx is true if there is a world in which ∃xEx
  • SEP reading on possibility and actuality
    Both parts are "from the viewpoint of a mind".Metaphysician Undercover

    You say “The place signified "Chicago" is not an imaginary thing, it is understood as real, actual.”

    The fact that I imagine the city of Chicago to be a real and actual place, means that the city of Chicago is in addition also an imaginary thing in my mind.
    ===========================================================
    So there is no way that we can get to the conclusion that the people in an imaginary world have a real and actual perspective.Metaphysician Undercover

    I cannot know that people in other possible worlds are real, but I can theorise that they are.

    I can never know for certain that the person I am talking to is as conscious as I am, but I can theorise that they are.
  • SEP reading on possibility and actuality
    Well, Homer is the author of the Iliad and the Odyssey. So presumable "Homer" designates that person whoever he may be.Ludwig V

    Continuing:

    1) Suppose a single person originated the Iliad, which was either written down or passed down as part of an oral tradition.
    2) Whoever originated the Iliad has been given the name “Homer”.
    3) Suppose, in fact, that the Iliad was originated by Hesiod.
    4) Hesiod had a friend, Homer, who was in fact a baker.

    Does the name “Homer” designate Hesiod, as for Kripke’s Rigid Designation, or does “Homer” refer to “the person who originated the Iliad”, as for Russell's Theory of Descriptions?
  • SEP reading on possibility and actuality
    The place signified "Chicago" is not an imaginary thing, it is understood as real, actual.Metaphysician Undercover

    This statement needs unpacking.

    The first part of the statement, “The place signified "Chicago" is not an imaginary thing” is from a mind-independent viewpoint.

    The second part of the statement, “it is understood as real, actual” is from the viewpoint of a mind.

    The first part of the statement linguistically clashes with the second part of the statement, making it difficult to answer.
    ==============================================================
    In the case of possible worlds, they are imaginary things, not real or actual, but possible.Metaphysician Undercover

    Again, this statement needs expanding. “For whom”?

    For Lewis’ Concretism, the statement is true from our viewpoint, in that from our viewpoint, these worlds are imaginary worlds, not real or actual.

    But the statement is not true from the viewpoint of those people living on these worlds, in that from their viewpoint, these worlds are not imaginary worlds, are real and actual.
  • SEP reading on possibility and actuality
    And the one being used in the article is Tarski’s Truth Definition.Banno

    :up:
  • SEP reading on possibility and actuality
    At any rate, anyone who chooses to take possible world analysis seriously ought to understand the dependency on coherence theory of truth.Relativist

    Yes, there are many different definitions of truth (SEP - Truth). The question of what establishes the truth of a statement then depends on which definition of truth is being used.
  • SEP reading on possibility and actuality
    Determinism only blocks alternative futures for this world, not alternative worlds altogether.Banno

    :up:
  • SEP reading on possibility and actuality
    So is the name "Homer" a rigid designator in this case?Ludwig V

    Wikipedia Homer notes
    The identity of "Homer" is a mystery, and scholars generally regard the ancient conception of a single author behind the Iliad and the Odyssey as a fictional narrative

    If everything I know about Aristotle is false, how do I know that Aristotle actually existed, or is in fact a fiction.

    If Aristotle, and perhaps Homer, never actually existed, yet Aristotle and Homer are rigid designators, then what is Aristotle and Homer actually designating.

    Using Kripke’s necessary a posteriori, it may be that in the future it is known without a doubt whether Aristotle and Homer were real or fictional. We may only know in the future what Aristotle and Homer are designating.

    Wikipedia Rigid Designator
    One puzzling consequence of Kripke semantics is that identities involving rigid designators are necessary. If water is H2O, then water is necessarily H2O.

    Wikipedia
    In modal logic and the philosophy of language, a term is said to be a rigid designator or absolute substantial term when it designates the same thing in all possible worlds in which that thing exists.

    However, if in the future it is discovered without doubt that Aristotle and Homer were not real but fictional, then today what is Aristotle and Homer designating? Presumably in that case, the names Aristotle and Homer are designating descriptions of Aristotle and Homer.
  • SEP reading on possibility and actuality
    What you learnt about Aristotle enables you to refer to AristotleLudwig V

    Wikipedia Naming and Necessity has the comment
    Scott Soames: In the philosophy of language, Naming and Necessity is among the most important works ever, ranking with the classical work of Frege in the late nineteenth century, and of Russell, Tarski and Wittgenstein in the first half of the twentieth century

    For me, the Aristotle I know has a cluster of properties. Even though “Aristotle” is a rigid designator, and refers to the actual Aristotle born 384BCE and died 322 BCE, none of the properties I know Aristotle by may in fact be true.

    However, Kripke argues for necessary a posteriori knowledge, that some truths can only be known through empirical observation. Therefore, even though my knowledge of Aristotle may be totally false, when I use the name Aristotle, it is still a rigid designator because the name still refers to the actual Aristotle.
  • SEP reading on possibility and actuality
    We produce a fictional idea, a possibility, then to make it fit within the possible worlds semantics, we assign concrete existence to it.Metaphysician Undercover

    I have never been to Chicago, but I imagine what it could be like, and I imagine it as an actual concrete place. I can imagine that the inhabitants of Chicago think of themselves as actual and concrete as I think of myself as concrete and actual.

    There is no logical problem with imagining something as being actual and concrete.

    For example, if you plan on a holiday to somewhere you have never been before, you presuppose that where you are going is an actual and concrete place. As with David Lewis, in this instance, you are also a Modal Realist, a Concretist.