Philos 2 Midterm

Time Travel, Cryogenics

One is cryogenically frozen for hundreds of years. Upon being woken, it seems from one's own point of view that hardly any time has passed

Time Travel, Coma

One is in a coma for a number of years and then awakes, at which point it seems from one's own point of view that hardly any time has passed

Validity

Premises true, conclusion must true

Parfit's Teletransporter

The initial version of the journey by teletransportation to Mars seems relatively unproblematic, even if currently technologically impossible. The memory requirement--If there are no memory relations -- whether direct or indirect -- between A and B, then A and B are not the same person. The memory guarantee--If there are memory relations -- whether direct or indirect -- between A and B, then A and B are the same person.

Which theory of causation rules out the possibility of backward causation?

The regularity theory

Omnipotence

all-powerfulness, almightiness

David Lewis

(1941 - 2001) Lewiswas an American philosopher who taught most of his life at Princeton. He made important contributions in philosophy of language, philosophy of mind, metaphysics, epistemology, and philosophical logic

In Favor of Free Will

(i) Feeling or experience of freedom (ii) We treat each other as if we were free We hold each other morally responsible for our actions. And we generally do not hold people responsible when they are not in control of their actions or those actions were not chosen freely Free will seems to be a condition on deserving credit for one's accomplishments Free will seems to be a condition on the value we accord to love and friendship (iii) In deciding what to do, we must treat ourselves as free. Free will requires the ability to do otherwise. Causal determinism implies the inability to do otherwise. Hence, they can't both be true

Solve a Paradox

-Find a false premise -Reject a premise theory -Show why the conclusion, which seems false, is actually true -Accept the conclusion -Reject the reasoning

Disjuctive Syllogism

1. Either p or Q 2. Not p 3. Therefore, Q

An Argument in Favor of Incompatibility

1. If determinism is true, then every human action is causally necessitated by prior events 2. If every action is causally necessitated, no one could have acted or chosen otherwise 3. One only has free will if one could have acted or chosen otherwise (C) Therefore, Causal Determinism is incompatible with the Existence of Free Will Hard Determinism: Accept (2) and (3), reject (1). There is no free will Libertarianism: Accept (1) and (3), reject (2). Some human actions or choices are not causally determined Compatibilism: Accept (1) and (2), reject (3). Reject the argument just given for Incompatibility.

Modus Tolles

1. If p, then Q 2. Not Q C. Therefore, not p Valid

Modus Ponens

1. If p, then Q 2. p C. Therefore, Q Valid

Fatalism vs. Free Will

1. Necessarily I will choose to eat a salad for lunch after class. (Fatalism) 2. If necessarily I will choose to eat a salad for lunch after class, then I could not have chosen to do anything else 3. Therefore, I could not have chosen to do anything else 4. My will is free with respect to an action, only if I could have chosen to do something else C) Therefore, my will was not free with respect to eating a salad after class.

Reject Incompatibility

1. Reject the claim that one is only free if one could have acted otherwise. 2. Reject the claim that if every action is causally necessitated, then no one could have acted otherwise.

Zeno of Elea

490 - 430 BC, Zeno's paradoxes are the earliest examples of a type of argument which, if successful, shows that some part of our ordinary picture of the world leads to contradiction Four Main Arguments -Achilles and the Tortoise Paradox -Racetrack Paradox -Paradox of Moving Bodies -Paradox of the Arrow

Causal Loops

A closed causal chain in which some of the causal links have a normal direction in time and others are reversed. The effect of a causal loop is also its cause. If A causes B and B also causes A, then A causes A. So A has no outside cause. Worry: Time travel into the past allows for causal loops. Causal loops are impossible. Therefore, time travel is impossible. If backward time travel is possible, then some things in the present can cause some things in the past. But all the things in the past together cause all the things in the present

Principle of Bivalence

A statement will be true or flase, declaritive sentence/talk about the world

Time Travel

A traveler departs and then arrives at her destination. The time elapsed for the traveler from departure to arrival is the duration of the journey. If she is a time traveler, intuitively the time that separates her departure from her arrival does not equal the duration of her journey Let's distinguish between EXTERNAL TIME and the PERSONAL TIME of the time traveler. Personal time is that which is measured, say, by the traveler's wristwatch. Her journey takes, say, an hour of her personal time. But the arrival is more than an hour after the departure in external time, if she travels toward the future; or the arrival is before the departure in external time if she travels toward the past, Think INTERSTELLAR Time travel takes place when there is a discrepancy between external time and personal time

Use/Mention

A word is "used" when we talk about the world by means of it Example: There is a tree in the garden A word that is "mentioned" often appear between qoutation marks or in italics Example: "Tree" is spelled with two "e"s.

Dualized Liar

A: B is true B: A is not true Suppose A is true 1) A is true Assumption 2) A (1), Disquotation 3) B is true (2), Def of A 4) B (3), Disquotation C) A is not true (4), Def of B (1) & (C) form a contradiction Suppose A is not true 1) A is not true Assumption 2) B (1), Def of B 3) B is true (2), Disquotation 4) A (3), Def of A C) A is true (4), Disquotation (1) & (C) form a contradiction

Existence of Free Will

Agents sometimes act and choose freely "Subject S's will is free with respect to performing action A if and only if S could have chosen to do other than A." If Subject S had no other choices other than action A, then Subject is not actually free because they could not make any other choice, they only had one option. Free will depends on choices, no choices, no free will. Example: Going to class, you could not go to class and take a nap instead, but if your only option was to go to class, then you don't have the choice to not go to class and thus you have no free will.

Analytic Statement Example

All mothers are parents

Probabilistic Theory of Causation

An event a causes an event b, if, given the occurrence of a, the probability of the occurrence of b is higher than the probability of the occurrence of b would have been if a had not occurred. (Hans Reichenbach) So, in this case, the fire causes the smoke just in case, given the occurrence of fire, the probability of smoke is higher than the probability of smoke would have been if fire had not occurred. Depending on how we define probability here, this may also have trouble distinguishing between causation and correlation.

Regularity Theory of Causation

An event a of type A causes an event b of type B if a and b actually occur and A-type events are regularly followed by B-type events. (David Hume) So, in this case, the fire causes the smoke just in case fire-events are regularly followed by smoke-events. Worry: This makes the connection between cause and effect too weak. Events may be correlated in this way because they have a common cause, even if they have no causal connection themselves.

Synthetic Propositions

Are true in virtue of how their meaning relates to the world, can be true but not based on virtue, must look at world Example: Bachelors are lonely and unhappy

Soundness

Arguement is valid and true premises

Aristotle and McTaggart

Aristotle's idea that future contingents have no truth values makes sense if we adopt McTaggart's A-series of time According to the A-series, the passage of time brings about changes in the truth values of a tensed statement. Aristotle could add, that the passage of time can give a truth value to a statement that did not have a truth value in the past But B-series properties are timeless and permanent A sentence whose only temporal expressions are B-series expressions is true at all times if it is true at any time. Given the B-series, it is not possible that there be fixed truths about the past and present, but not about the future

Parfit's Radical Response

At this stage, both materialism and the memory theory might seem to be in pretty bad shape. Parfit suggests a radical response to these problems. According to Parfit, when we talk about "personal identity" or "being the same person", we aren't really talking about an all-or-nothing thing. Rather, we are just talking about degrees of psychological similarity. So when I say that A and B are the same person, what I really mean is just: A and B are psychologically connected in certain interesting ways. So, in some sense, there's really no personal identity at all.

Circularity

Bad argument example, one or more premises relies for it's truth on the truth of the conclusion Example: X is true because of y Y is true because of X Doesn't give a reason to believe conclusion Trying to create a an argument based on the assumption that what you are argueing is already true Example: The Bible is true because it is God's truth, argument based on the fact that God is real

McTaggart

British philosopher, big idea-- 2 Conceptions of Time: A-Series and B-Series of Time Argument- 1. Time necessarily involves change 2. Only A-series can account for change 3. The A-series is contradictory C. Time is unreal Must have A-series to account for change, time must be describable, A-series is incoherent

Puzzles about Omniscience

But knowledge implies truth. Not everything is true and hence knowable. Challenges:-Can an omniscient being know an agent's future free actions? See lecture 6. If x is not a temporal and spatial being, how can it know the meaning of the indexical sentence "It is sunny here today"? Note that McTaggart argued that A-series expressions cannot be translated into B-series expressions. See Lecture 5. Def. 1: A being x is omniscient if and only if x knows everything. Def. 2: A being x is omniscient if and only if x knows all truths

Type

Category or class of object or event Example: "space," "time," "space," "time," "time", "time" answer 2

Are causal loops impossible? If they are, then travel into the past must be impossible too

Causal loops are strange but there is no reason to think that they are impossible. We seem to assume the possibility of many uncaused and inexplicable events. Examples: God, the Big Bang, the infinite past of the universe, etc?

Method of Counter Example

Conceivable possibility in which premises are true but conclusion is false

The modified memory theory defers from the original memory theory in that it:

Conceives of personal identity in terms of a chain of (one or more) "memory connections" as opposed to simply in terms of a single, direct "memory connection".

Law of NonContradiction

Contradictions cannot be true, nothing is nothing true and false

Explosion

Contradictions logically entail everything

Consider the series of letter grades (A+, A, A-, B+, etc) possible in this course. Is this series continuous or discrete?

Discrete

Physics and Time Travel, Einstein

Einstein. The time traveler steps into an "ordinary" rocket ship and flies off at near light speed on a round trip. When he returns to Earth, thanks to certain effects predicted by the Special Theory of Relativity, only a small amount of time has elapsed for him — he has aged only a few months — while a great deal of time has passed on Earth: it is now hundreds of years in the future of his time of departure This is important because relative to either of these frames, the other part of the spaceship's journey is itself "dilated" Thus, there is a sense in which the dilation of Earth-time relative to the first spaceship-frame is "canceled out" for the travelers by the dilation of that first frame relative to the second frame. And vice versa

Causal Determinism

Every event is causally determined to occur by some other events Causal determinism implies fatalism, so it is a kind of fatalism, as long as you think the starting conditions of the universe and the laws of nature are necessary. If other starting conditions are possible, then an entirely different future might have been determined

Incompatibilism

Existence of free will and casual determinism are incompatible, therefore, they can't all be true

The Problem of Fatalism

Fatalism is the view that whatever happens now and will happen in the future happens necessarily For the fatalist, because the present and future is fixed, or pre-ordained, our choices about what to do in a situation seem inconsequential. Note: Fatalism leaves it open whether there is any purpose guiding our fates. As described by Taylor, fatalism is more than just a view about the future, it is also an attitude towards the future that is grounded in a view about the future.

B-Series

First, we can relate various events to one another in terms of relations of "earlier than" or later than". This will provide us with a coherent ordering of these events. This gives us a B-series of events in time. The B-series is the relation between instants (a-series) There are five years between the beginning of the Korea War [1950] and Harry Truman's first inauguration as U.S. President [1945]. McTaggart claims that genuine temporal change is impossible on the B-series conception of time Earlier than, later than, dates/time, more objective, sentences which only contain b-series expressions are true always if ever Example: WWI before WWII

Happy-Face Solution

Get "rid" of paradox, show one of the premises aren't true or prove that are compatible

The divine voluntarist response to the Paradox of Omnipotence claims that:

God can make the laws of logic anything she wants them to be. Thus, God can do even things that seem contradictory by the standards of the logic we accept.

Contra Argument from Foreknowledge, Argument for fatalism

God's omniscience does not require us to accept premise (2), that necessarily God knows you will do x tomorrow When premise (2) is rephrased as follows:then the argument from foreknowledge becomes invalid But isn't God's omniscience a necessary attribute of God? And doesn't that imply that necessarily Gods knows what I will do before I choose to do it? Does this rule out free will? God knows that you will do x tomorrow It all depends on why the author of the book of my life (e.g. God) knows what he knows If the reason the author knows what I will do is because he controls my mind, then perhaps my will is not free But if the reason the author knows what I will do is because he is a time traveller from the future who closely observed me and wrote everything down then my will might still be free

Grandfather Paradox

Grandfather paradoxes arise whenever a time traveler goes into the past and prevents an event that is a pre-condition of the traveler making the backward time journey in the first place. Example: You have just finished building a time machine. You use this time machine to travel back twenty-four hours, cut the power-supply to your own laboratory so you can't finish the time machine that lets you go back in time to cut the power-supply ... Another example: A time traveler goes back in time and kills his grandfather before the grandfather has fathered children. If the grandfather dies at this point, then one of the time traveler's parents never exists. Hence the traveler can't be born and travel back to kill the grandfather ... and so on.

McTaggart and Time Travel

If the A-series of time is true, then time travel is harder to understand. On the A-series, the temporal position called "present" might move either backward (in the case of travel into the past) or forward (in the case of travel into the future). But it would not be possible to travel into a temporal position other than the present? And what would it even be to shift the present in this way? The B-series of time, which holds that all temporal positions, are equally real, makes it easier to understand time travel. On this view, travel in time is akin to travel in space in many ways

Interim Conclusion

If x can bring about anything (Def. 1), whether logically possible or impossible, then x could create a stone which x cannot lift. But then x could also lift the stone. So there is no objection to x's omnipotence, although we have to make sense of this conception of logic If the power of an omnipotent being x extends only to logically possible states of affairs (Def. 2), then x could not create a stone which x cannot lift. But since it is logically impossible that there be such a stone, this is no objection to x's omnipotence

Stephen Hawkins's argument against time travel

In any case, if backwards time travel is physically possible, isn't it surprising that we never encounter evidence of people traveling backwards in time?

Indexicals

Indexicals are words whose referent and meaning are determined by the context of the speaker - e.g. the time and space of speech. Examples: Pronouns: I, you, this, that-Adverbs: here, now, presently, today, yesterday, tomorrow Adjectives: my, your, past, present, future, left/right, up/down

False Dicotomy

Invalid argument 1. p or Q 2. p C. Therefore, not Q

Denying Antecdent

Invalid arguments 1. If p, then Q 2. Not p C. Therefore, not Q

Affirming Consequent

Invalid arguments 1. If p, then Q 2. Q C. Therefore, p

Aporia

Irresolvable internal contradiction in a concpet, arguement, or theory

What does Zeno's Arrow Paradox attempt to show?

It attempts to show that if space and time are discrete, then motion is impossible.

Disquotation

It seems to be part of the meaning of the word "true" that one can move freely between the claim that S and the claim that "S" is true. For example, to say that Karl is a professor and to say that it is true that Karl is a professor seems to be to say the same thing. This is formalized by philosophers in terms of the principle called disquotation, which says that one can infer that "S" is true from the claim that S and that one can infer that S from the claim that "S" is true: S <—> "S" is true

Posteriori

Justification is dependent on experience or empirical evidence Example: Some bachelors are happy

Liar Paradox

L1: This statement is false Suppose L1 is true; then it is as it says it is - i.e. it is false. So L1 is false. Suppose L1 is false. Well, false is just what it says it is, and a sentence that tells it the way it is is true. So L1 is true. So, if L1 is true, it is false; and if it is false, it is true. So it seems that L1 is neither true nor false. For if it were either, it would be both!

Paradox of Omnipotence

Let x be any being. 1. Either x can create a stone which x cannot lift, or x cannot create a stone which x cannot lift 2. If x can create a stone which x cannot lift, then, necessarily, there is at least one task which x cannot perform (namely, lift such a stone) 3. If x cannot create a stone which x cannot lift, then, necessarily, there is at least one task which x cannot perform (namely, create such a stone) 4. Hence, there is at least one task which x cannot perform 5. If x is an omnipotent being, then x can perform any task C) Therefore, x is not omnipotent

Reid's Paradox is an argument against which theory of personal identity?

Locke's memory theory

The Unreality of Time

McTaggart's Argument for the Unreality of Time 1. Time necessarily involves change. 2. Change is possible only in the A-series. 3. The A-series involves contradictions and is therefore unreal. C) Therefore, time is unreal. In effect, (1) and (2) together claim that time must be thought of as an A-series. And (3) claims that anything thought of in those terms is unreal.

Causation Correlation

Not Causation What the Tobacco Industry Wants Us to Believe Theories of Causation (2), smoking is "correlated" with lung cancer, but smoking doesn't cause lung cancer

Time Travel, Dateline

One boards an airplane, departs at 5pm on Monday, flies for twelve hours, and arrives at 5pm on Tuesday

Time Travel, Virtue

One enters a highly realistic, interactive virtual reality simulator in which some past era has been recreated down to the finest detail

Time Travel, Crystal

One looks into a crystal ball and sees what happened at some past time, or will happen at some future time

Time Travel, Lecture

One sits a lecture and time seems to slow to crawl. When the class ends one is amazed that so little time has passed

Hard determinism

Paradox of Free Will, concludes that freedom of the will is impossible because causal determinism is true Hard determinism says causal determinism is true and free will is false

Materialist

People are objects of matter, same body grown up This view is natural, because it fits with many things that we are inclined to say about ourselves For example, we say that we have a certain weight and height, and are in a specific place ... and what could occupy a place, and have a weight and height, other than a physical thing? Advantage: Doesn't have to postulate a new entity Counterexample: Prince and the Cobbler, this seems to be a problem for materialist views of human persons. If Locke is right, and we can coherently imagine cases in which two persons "swap bodies", then it seems that we cannot be identical to our bodies

Sydney Shoemaker's counterexample to McTaggart's

Premise One Suppose a universe of three regions, in which the observers in each region notice periods of complete changelessness in the other two, time must be possible for change to happen The periods of standstill are regular, lasting in Region A for one year out of every three, in Region B for one year out of every four, and in Region C for one year out of every five Thus there will be changelessness throughout the universe for one year out of every sixty years. The total standstill will not be noticed by anyone but the inhabitants can infer it So a total standstill is possible.

David Lewis's Solution of the Grandfather Paradox

Premises (1) and (2) on slide #24 are both true.They do not contradict one another.The term "can" in both premises mean different things. The Grandfather paradox rests on an equivocation about the meaning of "can." When we say that somebody "can" do something, we mean that they have the capacity to do it, holding certain things fixed. Which things we hold fixed will depend upon context. Unlike dogs and cats, I can speak a foreign language, like Urdu. So there is a sense in which I can speak Urdu. But don't take me as your translator when you go to Pakistan, because I can't speak Urdu. I have never learned it. When we say "Karl can speak Urdu", we are only holding fixed my brain's linguistic potentialities — we are saying that Karl could learn it. When we say "Karl can't speak Urdu", we are holding fixed my actual knowledge of languages — we are saying that he doesn't currently speak it. What I can do, relative to one set of facts, I cannot do, relative to another set of facts

Inductive

Premises supports the truth of conclusion but it doesn't guarantee it Strength Example: premise 1 and 2 can be true but the conclusion may be false

Unhappy-Face Solution

Reject concept, recognize the contradiction, cannot escape paradox, irresolvable tension between premises and conclusion

Brain Bisection

Relates to materialist and psychological theorists Mr. Red and Mr. Blue, So any sensory data about the environment available to, for example, the left hemisphere, will not be available to guide the movements of the left hand, which is controlled by the right hemisphere. Information available only to the right hemisphere will not be reportable in speech, since speech is controlled by the left hemisphere Ownership: Every conscious experience must be an experience of someone. Awareness: If someone has a conscious experience, it must be at least in principle possible for them to be aware of that experience Red stimulus presented to the right half of their visual field, and a blue stimulus presented to the left half of their visual field If you ask the subject what color they see, they will say "Red", since this was the color presented to the part of the eye which feeds input to the left hemisphere of the brain, which controls speech. So it is clear that there is a conscious experience of red; so, by Ownership, there must be someone who is having this experience. Let's call this person "Mr. Red." If you put a pen in the left hand of the subject, and ask what color was just seen, that hand will write "Blue." So it seems that there must have been a conscious experience of blue - otherwise, how would the hand know what color to write? But if there is a conscious experience of blue, by Ownership someone must have had this experience. Let us call the person who has this experience "Mr. Blue." It seems to follow from Awareness that they are not the same person. After all, if you ask Mr. Red whether he has had any experience of blue, he will say "No." And no amount of introspection on his part will allow him to remember having a conscious experience of this sort; and of course this is not because he forgot having the experience, but because he was never aware of having it. But then, by Awareness, he didn't have it. In short, there seem to be two distinct streams of consciousness in this person. Hence it seems that Mr. Red≠Mr. Blue. So there are two persons in the body of the split brain patient

Psychology

Same memories, same psychology, psychological contiuity Advantage: Doesn't have to postulate a new entity

Memory Theory

Same person if and only if they have the same memories Reid's objection: At 20 years old a man could have memories of being 5, however, at 50 years old, the man may only remember memories dating back to his 20s, does that mean he isn't the same person x=y y=x C. x=z However 50=20 20=5 50=5? No because the man cannot remember being 5, contradiction

Self-Referential

Self-reference isn't essential to the paradox

Arguement

Series of statements where the last statement supposedly follows from or is supported by the premise Must have true premises a=b, b=c, so a must = c

Synthetic Statement Example

Social Science Hall has 4 sides

Dualist

Soul responsible for free will, souls grow up, a person is just a mind, must have same soul to be considred idetical Advantage: Accounts for body switching

Racetrack Paradox

Space and time are CONTINUOUS The Racetrack argument is meant to show that it is impossible to move any finite distance in a finite time Imagine that you are trying to move from point A to point B. Suppose C is the midpoint of the distance from A to B. It seems that you have to first get from A to C, before you can get from A to B. Now suppose that D is the midpoint between A and C; just as above, it seems that you have to first get from A to D before you can get from A to C. Any distance is divisible into infinitely many smaller distances It is impossible to traverse infinitely many distances in a finite time. C) It is impossible to move from one point to another in a finite time The sum of an infinite number of finite times must be infinte, WRONG, ad 1/2+1/4+1/8+1/16...=1 The sum won't add to infinite because the distance is getting smaller You can say space and time is discrete

Paradox of the Arrow

Space and time are DISCRETE Consider an indivisible moment in time. It seems that it cannot since, if it did, the instant would be divisible — the arrow would have to be in one place for one part of the instant, and in another part for another. But if instants have parts, then they are not indivisible There is NO time between an indivisible instant, therefore, the arrow cannot "move" between instants

Paradox of Moving Bodies

Space and time are DISCRETE There can be points in space which are genuinely adjacent, in the sense that there are no points in between them The points can switch spots without "passing" each other or becoming "even" with each other because the "point" at which they would become "even" does not exist, instead the point jump past each other in their respective spots in time Can deny that spacee and time are discrete by stating it is conintious A B C ----> move one space to the left 1 2 3 a b c----> move one space too A B C cannot go by without being 1 2 3 even, teleporting a b c Resolve it by stating that on a submolecular level, things may not be even with each other because they skip between the individsibleunits of space and time. However, in terms of bigger objects of matter, like humans or apples, it is possible for something to lool even with another object, or pass an object evenly.

Token

Specific instance or occurrence of a type of object or event Example: "space," "time," "space," "time," "time", "time" answer 6

McTaggart's 1st Rejoinder

The B-theoretical notion of change is not genuine change. The B-series fact that the poker is hot on Monday and is cold on Tuesday is a timeless fact. And such facts (once made fully explicit) never change. Suppose that when we say of the poker on Monday 10/09/17 that it is hot, all we attribute to the poker is the timeless B-series property of being hot on Monday 10/09/17. Then, on Tuesday 10/10/17 it is still the case that the poker has the property of being hot on Monday 10/09/17. Hence, the poker's B-series properties have not changed between Monday and Tuesday

McTaggart's 2nd Rejoinder

The B-theoretical notion of change is unable to differentiate between temporal and spatial change. Compare the idea that a highway has four lanes in one section and eight lanes in another. This involves a sort of "spatial change". But the sort of change that the B-series can capture seems fundamentally the same - only with a different dimension along which the facts vary.

Slippery Slope Fallacy

The assumption that something is wrong because it is similar to something that is wrong

Argument from Authority

The claim that the speaker is an expert, so it should be trusted, be skeptical

What will actually prevent the time traveler from killing his grandfather?

The failure to kill his grandfather will be caused by strange coincidences: His gun jams, a noise distracts him, he slips on a banana peel, he accidentally shoots someone else, etc

Tarski's solution

The liar paradox does not arise if "true" and "false" cannot not apply to the very sentences these terms occur in, but instead apply only to sentences in a different language - or part of the language On this view, no language can contain a coherent word "true" which can apply to all of its own sentences. If a language contains a word "true", it must apply only to sentences within a smaller part of that language, which we can call the object-language. The words "true" and "false" may not occur in the object-language. They may only occur in what is called the meta-language. The meta-language includes all of the object-language - plus it can talk about the truth values of the object-language MAY NOT BE GOOD ENOUGH BECAUSE IT OVERGENERALIZES

Attempts to Solve Liar Paradox

The liar statement is neither true nor false--Proposal: If the acceptance/rejection of a statement involving "true" or "false" is explained by the acceptance/rejection of a statement that does not involve "true" or "false", call that statement "grounded." E.g. "Grass is green" is true. If not, call that statement "ungrounded." E.g. This is sentence is true. Suppose we say that ungrounded statements are neither true nor false. The Liar statement is ungrounded, and therefore is neither true nor false The liar sentence is both true and false (Dialetheism - Buddhism)--Problems: As with dialetheism, this proposal rejects an element of classical logic: the principle of bivalence. The liar statement is just meaningless b/c it is self-referential--To claim that the liar statement has no truth value might seem to be tantamount to saying that it is meaningless. Problem: If the liar statement was meaningless how come that we can understand it and discuss it? The liar statement is false The liar statement is ill-formed or meaningless b/c it uses a non- hierarchical notion of truth The liar sentence is "kind of true"

Modified Memory Theory

The modified memory theory of persons: x and y are the same person if and only if either: 1) x has memories of y (or vice versa), or (2) there is some series of persons connecting x and y which is such that each person in the series has memories of the immediately preceding person in the series The memory requirement: If there are no memory relations - whether direct or indirect - between A and B, then A and B are not the same person. The memory guarantee: If there are memory relations - whether direct or indirect - between A and B, then A and B are the same person

Physics and Time Travel, Gödel

The time traveler steps into an ordinary rocket ship (not a special time machine) and flies off on a certain course. At no point does he disappear (as in Leap)—yet because of the structure of spacetime (as conceived in the General Theory of Relativity), the traveler arrives at a point in the past of his departure.•GTR = STR + the idea that spacetime is curved (gravity) On some possible models of GTR, this curvature produces "closed causal loops" such that it is possible to travel along such a loop and arrive where one started. Loops of this sort would represent a way of traveling backwards in time. (Compare how someone can travel continuously westwards, and arrive to the east of his departure point, thanks to the overall curved structure of the surface of the earth.)

Achilles and the Tortoise Paradox

This argument is supposed to show that if space and time are CONTINUOUS, then the motion is impossible. It always takes Achilles some finite amount of time to catch up to where the tortoise was, and during that finite amount of time, the tortoise will always have covered some distance. But we know that this is absurd. Indeed, it seems that if the motion is possible at all, it is possible for one thing to catch another thing from behind. But this seems to be what Zeno has shown to be impossible! The Achilles paradox attempts to show that nothing can ever catch anything else from behind (so long as the former is moving at a finite speed and the latter never stops moving) The sum of an infinite number of finite times must be infinte, WRONG, add 1/2+1/4+1/8+1/16...=1 The sum won't add to infinite because the distance is getting smaller You can also say space and time is discrete

Dual Liar and Self-Referential Statements

This solution goes too far. Self-reference by itself is not the problem. There are many informative and unproblematic self-referential statements. E.g. "This statement is made by means of an English sentence." Various useful theses have to be formulated by means of self-referential statements. E.g. "Meaningful declarative statements have some truth-value or other."

Backward Causation Worry

Time travel into the past necessarily involves backward causation with respect to external time Example: The traveler punches her face before she departs and causes her eye (post travel) to blacken centuries ago. The idea of the effect preceding its cause (in external time) is incoherent. Therefore, time travel is incoherent.

Necessary/Sufficient Conditions

To say that X is a necessary condition for Y is to say that it is impossible to have Y without X. In other words, the absence of X guarantees the absence of Y Example: Having four sides is necessary to be a square

Necessary Truths

True in all possible worlds

Contingent Truths

True in somepossible worlds and false in others

Analytic Propositions

True in virtue of how their meaning relates to the world Example: An unmarried man is a bachelor

Deductive

Truth of premises guarantees the truth of the conclusion Validity and soundness

Strength

Truth of premises make conclusion more likely, for inductive argument, premises support conclusion but don't guarantee it

Invalid Arguement Example

Vegetarians don't eat pork, Gandhi didn't eat pork, Gandhi is a vegetarian Doesn't guarantee that Gandhi was a vegetarian

Ambiguity

When a term can mean several different things, can cause fallacy of equivocation when different premises of a single argument use different meaning of the term Example: Bank has money, a river bank must be full of money

Omnibenevolence

all-goodness

Omniscience

all-knowing

Omnipresence

the state of being widespread or constantly encountered

An Aristotelian Argument for Fatalism

1. Either it is true that E will happen, or it is true that E will not happen 2. If it is true that E will happen, then E will be in the past 3.If E will be the past, then E will be necessary Therefore, it is true that E will happen, then E will be necessary. (2,3) 5) 4. If E will be necessary, then E is necessary now 5. Therefore, if it is true that E will happen, then E is necessary now. (4,5)7) 6. And, by the same reasoning, if it is true that E will not happen, then E not happening is necessary now. C) Therefore, either E happening is necessary now or E not happening is necessary now. (1, 6, 7)

Hypothetical Syllogism

1. If p, then Q 2. If p, then Q C. Therefore, if p, then r

Propositions

A proposition is the meaning or content of a declarative sentence or thought Propositions are true or false, a single proposition can be expressed in many ways Propositions are different from actions (talking, thinking, drawing), by ich they are expressed, propositions are different from the words, sounds, symbols, or brain states by which they are expressed Propositions are independent of the language used to express them

Discrete Series

A series that is not continuous is discrete, example: natural numbers

Personal Identity Theory

A theoryof what it takes for two people (at different times) A and B to be the same person

A or B Series Statement: The Obama administration is in the past.

A-Series

Special Relativity

According to Special Relativity, duration is relative to a frame of reference — and in particular, relative to the velocity of that frame compared to the velocity of what is being timed. This creates an effect called time dilation, in which the time passing at F relative to G slows down as the speed of F relative to G increases

Causation as Counterfactual Dependence

An event a causes an event b, if, had a not occurred, then b would not have occurred. (David Lewis) So, in this case, the fire causes the smoke just in case the following is true: if the fire had not occurred, the smoke would not have occurred. The idea here is that these sorts of "counterfactual" claims characterize the dependence of the effect on the cause

Paradox

Apparently, unacceptabe conclusion derived from apparently acceptable reasoning from apparently acceptable premises

Argument from Foreknowledge, argument for fatalism

Argument from Foreknowledge Necessarily, if God (or anyone else) knows you will do x tomorrow, then you will do x tomorrow. Necessarily, God knows that you will do x tomorrow. C)Therefore, it is necessary that you do x tomorrow. The argument is valid. But is it sound? Note, that this argument (unlike the argument from Determinism), does not rely on a scientific conception of reality.

Arguement Ad Hominem

Attacking the person instead of argument

Continuous Series

Between every two members of the series, there is another member of that series, example: rational numbers

If you choose an to this question at random, what is the chance you will be correct? A. 25% B. 50% C. 0% D. 75%

C.0%

Reasons to believe in Causal Determinism

Causal determinism is the view that the state of the world at a given time (together with the laws of nature) wholly determines the state of the world at the next moment. Every event that occurs, including human action, is entirely the result of earlier causes and natural laws. The state of the universe, plus the laws of nature,determine a single unique future

Entailment

Conclusion follows validity from the premises If something entails another statement/proposition, that means the og statement guarentees the truth of the following statement Cannot have a "fire" without "smoke" & if there is "smoke" there is probably a "fire."

Sci-fi Time Travel Scenarios

Doctor: Doctor Who steps into his Tardis in 2017. Observers outside the machine see it disappear. Inside the Tardis, time seems to Doctor Who to pass for ten minutes. Observers in 1984 (or 3072) see a phone booth appear out of nowhere. Doctor Who steps out. Leap: The time traveler takes hold of a special device and suddenly disappears; he appears at an earlier (or later) time. Unlike in Doctor, the time traveler experiences no lapse of time between his departure and arrival: from his point of view, he instantaneously appears at the destination time

How does Lewis respond to the Grandfather paradox?

He claims that the appearance of a paradox is caused by a shift between two different meanings of the word "can".

What is Aristotle's strategy for avoiding fatalism?

He denies that future contingents have truth conditions

Genetic Fallacy

If an argument has some particular origin, the argument must be right/wrong

The free will response to the Problem of Evil claims that

In order to create beings with free will, God must allow these creatures to do evil

A-Series

Includes the properties of being past, present and future. A-series expressions include such words as "present," "past," "future," "today," "tomorrow," and "five weeks ago". These expressions are INDEXICALS In this sense, we can think of the A-series expressions as "centered" on the present. They describe things in relation to the time it is now A-seris is an instant in time A-series sentence: It is sunny today Past, present, future, "is currently," was, will be, yesterday

Vague

It's meaning doesn't settle exactly what it means Example: John is rich, but how rich?

Priori

Knowledge is independent of experience Example: All bachelors are unmarried

Libertarianism

Libertarianism says that free will is true and causal determinism is false

Science and Determinism

Macro-level scientific theories seem to imply that macro-level events follow deterministic laws. In particular, the laws of neurobiology and psychology seem to be broadly deterministic So thought of it in this way, our choices seem to be determined by prior events in accordance with these laws. On the micro-level (the subatomic level), quantum mechanics tells us that the laws are non-deterministic or probabilistic. But this doesn't seem to be much help in the present context. For being told that our choices the products of probabilistic laws is akin to being told that they are random (within certain bounds). And randomness also seems incompatible with free will