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All the ideas for 'fragments/reports', 'The Concept of Truth for Formalized Languages' and 'Intro to Contemporary Epistemology'

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90 ideas

1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
As coherence expands its interrelations become steadily tighter, culminating only in necessary truth [Dancy,J]
     Full Idea: As our system grows in coherence, the interrelations between its parts becomes tighter and tighter;… at the limit contingent truth vanishes, leaving only necessary truth.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 14.7)
3. Truth / A. Truth Problems / 2. Defining Truth
Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach]
     Full Idea: Tarski's Theorem states that under fairly generally applicable conditions, the assumption that there is a definition of truth within a given theory for the language of that same theory leads to a contradiction.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 1
     A reaction: That might leave room for a definition outside the given theory. I take the main motivation for the axiomatic approach to be a desire to get a theory of truth within the given theory, where Tarski's Theorem says traditional approaches are just wrong.
Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten]
     Full Idea: Tarski's Theorem on the undefinability of truth says in a language sufficiently rich to talk about itself (which Gödel proved possible, via coding) the liar paradox can be carried out.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 02.2
     A reaction: The point is that truth is formally indefinable if it leads inescapably to contradiction, which the liar paradox does. This theorem is the motivation for all modern attempts to give a rigorous account of truth.
'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski]
     Full Idea: The possibility of a consistent use of 'true sentence' which is in harmony with the laws of logic and the spirit of everyday language seems to be very questionable, so the same doubt attaches to the possibility of constructing a correct definition.
     From: Alfred Tarski (The Concept of Truth for Formalized Languages [1933], §1)
     A reaction: This is often cited as Tarski having conclusively proved that 'true' cannot be defined from within a language, but his language here is much more circumspect. Modern critics say the claim depends entirely on classical logic.
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach]
     Full Idea: Tarski's Theorem applies to any sufficient precise version of the correspondence theory of truth, and all the other traditional theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 1
     A reaction: This is the key reason why modern thinkers have largely dropped talk of the correspondence theory. See Idea 16295.
The correspondence theory also has the problem that two sets of propositions might fit the facts equally well [Dancy,J]
     Full Idea: The correspondence theory as well as the coherence theory has the problem of more than one set of truths. Why can't two sets of propositions "fit the facts" equally well?
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.2)
3. Truth / D. Coherence Truth / 1. Coherence Truth
Rescher says that if coherence requires mutual entailment, this leads to massive logical redundancy [Dancy,J]
     Full Idea: Rescher complains that if coherence requires mutual entailment, then what is entailed is logically redundant, and the whole system is infected with mutual redundancy.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.1)
If one theory is held to be true, all the other theories appear false, because they can't be added to the true one [Dancy,J]
     Full Idea: From the point of view of someone with a theory every other theory is false, because it cannot be added to the true theory.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.2)
3. Truth / D. Coherence Truth / 2. Coherence Truth Critique
Even with a tight account of coherence, there is always the possibility of more than one set of coherent propositions [Dancy,J]
     Full Idea: No matter how tight our account of coherence we have to admit that there may be more than one set of coherent propositions (as Russell pointed out (1907)).
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.2)
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten]
     Full Idea: Tarski emancipated truth theory from traditional philosophy, by no longer posing Pilate's question (what is truth? or what is the essence of truth?) but instead 'how is truth used?', 'how does truth function?' and 'how can its functioning be described?'.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 02.2
     A reaction: Horsten, later in the book, does not give up on the essence of truth, and modern theorists are trying to get back to that question by following Tarski's formal route. Modern analytic philosophy at its best, it seems to me.
Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach]
     Full Idea: Tarski did not settle for a definition of truth, taking its adequacy for granted. Rather he proposed an adequacy criterion for evaluating the adequacy of definitions of truth. The criterion is his famous Convention T.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
     A reaction: Convention T famously says the sentence is true if and only if a description of the sentence is equivalent to affirming the sentence. 'Snow is white' iff snow is white.
Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski]
     Full Idea: Tarski does not tell us how to apply his concept of truth to a new case, whether the new case is a new language or a word newly added to a language. This is because enumerating cases gives no clue for the next or general case.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: His account has been compared to a telephone directory. We aim to understand the essence of anything, so that we can fully know it, and explain and predict how it will behave. Either truth is primitive, or I demand to know its essence.
Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski]
     Full Idea: Tarski defined the class of true sentences by giving the extension of the truth predicate, but he did not give the meaning.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: This is analogous to giving an account of the predicate 'red' as the set of red objects. Since I regard that as a hopeless definition of 'red', I am inclined to think the same of Tarski's account of truth. It works in the logic, but so what?
Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady]
     Full Idea: Tarski's account doesn't hold for natural languages. The general notion of truth is replaced by "true-in-L", where L is a formal language. Hence truth is relativized to each artificial language.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Paul O'Grady - Relativism Ch.2
     A reaction: This is a pretty good indication that Tarski's theory is NOT a correspondence theory, even if its structure may sometimes give that impression.
Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski]
     Full Idea: Tarski has to define truths so as not to make explicit the relation between a true sentence and an obtaining state of affairs. ...He has to list each sentence separately, and simply assign it a state of affairs.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.8
     A reaction: He has to avoid semantic concepts like 'reference', because he wants a physicalist theory, according to Kirkham. Thus the hot interest in theories of reference in the 1970s/80s. And also attempts to give a physicalist account of meaning.
Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack]
     Full Idea: Tarskian semantics says that a sentence is true iff it is satisfied by every sequence, where a sequence is a set-theoretic individual, a set of ordered pairs each with a natural number as its first element and an object from the domain for its second.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Keith Hossack - Plurals and Complexes 3
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess on Tarski]
     Full Idea: In Tarski's theory of truth, although the notion of truth is applicable only to closed formulas, to define it we must define a more general notion of satisfaction applicable to open formulas.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by John P. Burgess - Philosophical Logic 1.8
     A reaction: This is a helpful pointer to what is going on in the Tarski definition. It culminates in the 'satisfaction of all sequences', which presumable delivers the required closed formula.
Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt]
     Full Idea: Tarski invoked the notion of a sentential function, where components are replaced by appropriate variables. A function is then satisfied by assigning objects to variables. An assignment satisfies if the function is true of the things assigned.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Ian Rumfitt - The Boundary Stones of Thought 3.2
     A reaction: [very compressed] This use of sentential functions, rather than sentences, looks like the key to Tarski's definition of truth.
We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten]
     Full Idea: The truth predicate, says Tarski, should be defined in terms of the more primitive satisfaction relation: the relation of being 'true of'. The fundamental notion is a formula (containing the free variables) being true of a sequence of objects as values.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 06.3
For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham]
     Full Idea: Tarski, a physicalist, reduced semantics to physical and/or logicomathematical concepts. He defined all semantic concepts, save satisfaction, in terms of truth. Then truth is defined in terms of satisfaction, and satisfaction is given non-semantically.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.1
     A reaction: The term 'logicomathematical' is intended to cover set theory. Kirkham says you can remove these restrictions from Tarski's theory, and the result is a version of the correspondence theory.
Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham]
     Full Idea: Tarski's great insight is find another property, since open sentences are not truth. It must be had by open and genuine sentences. Clauses having it must generate it for the whole sentence. Truth can be defined for sentences by using it.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.4
     A reaction: The proposed property is 'satisfaction', which can (unlike truth) be a feature open sentences (such as 'x is green', which is satisfied by x='grass'),
Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson]
     Full Idea: Tarski turned his axiomatic characterisation of satisfaction into an explicit definition of the satisfaction-predicate using some fancy set theoretical apparatus, and this in turn leads to the explicit definition of the truth predicate.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 7
3. Truth / F. Semantic Truth / 2. Semantic Truth
Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach]
     Full Idea: Tarski's proof of the definability of truth allowed him to establish truth as a respectable notion by his standards.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski]
     Full Idea: Tarski defined various predicates of the form 's is true in L', each applicable to a single language, but he failed to define a predicate of the form 's is true in L' for variable 'L'.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: You might say that no one defines 'tree' to be just 'in English', but we might define 'multiplies' to be in Peano Arithmetic. This indicates the limited and formal nature of what Tarski was trying to achieve.
Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski]
     Full Idea: Every really adequate theory of truth should also prove the law of non-contradiction. Therefore Tarski's notion of adequacy in Convention T fails to capture the intuitive notion of adequacy he is after.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
     A reaction: Tarski points out this weakness, in a passage quoted by Halbach. This obviously raises the question of what truth theories should prove, and this is explored by Halbach. If they start to prove arithmetic, we get nervous. Non-contradiction and x-middle?
Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack]
     Full Idea: Tarski says "we may remain naïve realists or idealists, empiricists or metaphysicians… The semantic conception is completely neutral toward all these issues."
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Susan Haack - Philosophy of Logics 7.5
Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H]
     Full Idea: Tarski work was to persuade physicalist that eliminating semantics was on the wrong track, and that we should explicate notions in the theory of reference nonsemantically rather than simply get rid of them.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Hartry Field - Tarski's Theory of Truth §3
A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski]
     Full Idea: We need to add theories of primitive reference to Tarski's account if we are to establish the notion of truth as a physicalistically acceptable notion.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Hartry Field - Tarski's Theory of Truth §4
     A reaction: This is the main point of Field's paper, and sounds very plausible to me. There is something major missing from Tarski, and at some point there needs to be a 'primitive' notion of thought and language making contact with the world, as it can't be proved.
Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read]
     Full Idea: Besides a theory of truth of his own, Tarski developed a theory of theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Stephen Read - Thinking About Logic Ch.1
     A reaction: The famous snow biconditional is the latter, and the recursive account based on satisfaction is the former.
Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki]
     Full Idea: Tarski's analysis of the concept of 'truth' ...is given a precise treatment as a particular relation between syntax (language) and semantics (the world).
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Michal Walicki - Introduction to Mathematical Logic History E.1
     A reaction: My problem is that the concept of truth seems to apply to animal minds, which are capable of making right or wrong judgements, and of realising their errors. Tarski didn't make universal claims for his account.
Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski]
     Full Idea: The Tarskian account of truth neglects the atomic sentences.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Mulligan/Simons/Smith - Truth-makers §1
     A reaction: Yes! The whole Tarskian edifice is built on a foundation which it is taboo even to mention. If truth is just the assignment of 'T' and 'F', that isn't even the beginnings of a theory of 'truth'.
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten]
     Full Idea: Tarski's work is the earliest axiomatic theory of truth that meets minimal adequacy conditions.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 01.1
     A reaction: This shows a way in which Tarski gave a new direction to the study of truth. Subsequent theories have been 'stronger'.
Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach]
     Full Idea: Tarski preferred a definition of truth, but from that an axiomatisation can be extracted. His induction clauses can be turned into axioms. Hence he opened the way to axiomatic theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is invariant under arbitrary permutations, so it seems to be a logical term [Tarski, by McGee]
     Full Idea: Tarski showed that the only binary relations invariant under arbitrary permutations are the universal relation, the empty relation, identity and non-identity, thus giving us a reason to include '=' among the logical terms.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Vann McGee - Logical Consequence 6
     A reaction: Tarski was looking for a criterion to distinguish logical from non-logical terms, since his account of logical validity depended on it. This idea lies behind whether a logic is or is not specified to be 'with identity' (i.e. using '=').
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
A name denotes an object if the object satisfies a particular sentential function [Tarski]
     Full Idea: To say that the name x denotes a given object a is the same as to stipulate that the object a ... satisfies a sentential function of a particular type.
     From: Alfred Tarski (The Concept of Truth for Formalized Languages [1933], p.194)
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
Tarski built a compositional semantics for predicate logic, from dependent satisfactions [Tarski, by McGee]
     Full Idea: Tarski discovered how to give a compositional semantics for predicate calculus, defining truth in terms of satisfaction, and showing how satisfaction for a complicated formula depends on satisfaction of the simple subformulas.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Vann McGee - Logical Consequence 4
     A reaction: The problem was that the subformulas may contain free variables, and thus not be sentences with truth values. 'Satisfaction' can handle this, where 'truth' cannot (I think).
Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham]
     Full Idea: Tarski invented a formal semantics for quantified predicate logic, the logic of reasoning about mathematics. The heart of this great accomplishment is his theory of truth. It has been called semantic 'theory' of truth, but Tarski preferred 'conception'.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.1
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach]
     Full Idea: Tarski's distinction between object and metalanguage forms the basis of model theory.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 11
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Tarski, by Fisher]
     Full Idea: In Tarski's account of truth, self-reference (as found in the Liar Paradox) is prevented because the truth predicate for any given object language is never a part of that object language, and so a sentence can never predicate truth of itself.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Jennifer Fisher - On the Philosophy of Logic 03.I
     A reaction: Thus we solve the Liar Paradox by ruling that 'you are not allowed to say that'. Hm. The slightly odd result is that in any conversation about whether p is true, we end up using (logically speaking) two different languages simultaneously. Hm.
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman on Tarski]
     Full Idea: Tarski's theory of truth has been most influential in eventually creating a shift from the entirely syntactic way of doing things in metamathematics (promoted by Hilbert in the 1920s, in his theory of proofs), towards a set-theoretical, semantic approach.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Feferman / Feferman - Alfred Tarski: life and logic Int III
7. Existence / D. Theories of Reality / 2. Realism
Realism says that most perceived objects exist, and have some of their perceived properties [Dancy,J]
     Full Idea: Realism in the theory of perception is that objects we perceive usually do exist, and retain some at least of the properties we perceive them as having.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.2)
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
A pupil who lacks confidence may clearly know something but not be certain of it [Dancy,J]
     Full Idea: Why isn't certainty required for knowledge? Because we are often prepared to allow that someone does in fact have knowledge when the person is so uncertain they would not claim knowledge for themselves (the 'diffident schoolboy').
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 2.1)
11. Knowledge Aims / B. Certain Knowledge / 3. Fallibilism
If senses are fallible, then being open to correction is an epistemological virtue [Dancy,J]
     Full Idea: In my view, once we admit that our beliefs about our sensory states are not infallible, incorrigibility would be a vice rather than a virtue.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.3)
     A reaction: This seems to be axiomatic among modern philosophers, and I certainly agree with it.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / a. Naïve realism
Naïve direct realists hold that objects retain all of their properties when unperceived [Dancy,J]
     Full Idea: The naïve direct realist holds that unperceived objects are able to retain properties of all the types we perceive them as having, which includes not only a shape and a size, but also a colour, a taste and a smell.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.3)
     A reaction: This I take to be a completely untenable view, if we are including the qualia of red, sweet or pungent among the properties. It seems uncontroversial that objects retain the capacity to cause redness etc. when they are unperceived.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
Scientific direct realism says we know some properties of objects directly [Dancy,J]
     Full Idea: The scientific direct realist accepts the directness of our perception of the world, but restricts his realism to a special group of properties, ..not including those which are dependent for their existence upon the existence of a perceiver.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.3)
     A reaction: Dancy goes on to say that this distinction is a 'close relative' of Locke's primary/secondary distinction. Am I a direct realist or a representative realist about primary properties? Maybe the distinction dissolves as we unravel the true process.
Maybe we are forced from direct into indirect realism by the need to explain perceptual error [Dancy,J]
     Full Idea: Direct realism is unlikely to be able to provide an explanation of perceptual error without collapsing into indirect realism.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.3)
     A reaction: If there is an error, there must be two things which don't match: the perception, and the reality. This seems to me a powerful reason for preferring indirect or representative realism. I like the idea that we make mental 'models' (rather than inferences).
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / c. Representative realism
Internal realism holds that we perceive physical objects via mental objects [Dancy,J]
     Full Idea: Indirect realism holds that in perception we are indirectly aware of the physical objects around us in virtue of a direct awareness of internal, non-physical objects.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.4)
     A reaction: This may be a slightly prejudicial definition which invites insoluble questions about the ontological status of the internal 'objects'. It seems to me obvious that we create some sort of inner 'models' or constructions in the process of perception.
Indirect realism depends on introspection, the time-lag, illusions, and neuroscience [Dancy,J, by PG]
     Full Idea: The four standard reasons for preferring indirect to direct realism are introspection of our mental processes, the time-lag argument, the argument from illusion, and the findings of neuroscience.
     From: report of Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.4) by PG - Db (ideas)
     A reaction: Ultimately one's views about realism depend on one's views of the mind/brain, and it is the last of the four reasons that sways me. We know enough about the complexity of the brain to accept that it represents reality, with no additional ontology.
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Phenomenalism includes possible experiences, but idealism only refers to actual experiences [Dancy,J]
     Full Idea: Phenomenalism talks about actual and possible experiences, whereas idealism confines itself to the actual experiences.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 9.5)
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / a. Idealism
Eliminative idealists say there are no objects; reductive idealists say objects exist as complex experiences [Dancy,J]
     Full Idea: The eliminativist idealist holds that there is no such thing as a material object; there is nothing but experience (idea, sensation). The reductive idealist holds that there are material objects, but they are nothing other than complexes of experience.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.6)
     A reaction: Dancy says Berkeley was of the latter type. The distinction doesn't strike me as entirely clear. I can't make much sense of the words 'are' or 'exist' in the second theory. To say it is only experiences translates (to me) as 'doesn't exist'.
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
Extreme solipsism only concerns current experience, but it might include past and future [Dancy,J]
     Full Idea: Extreme solipsism only considers present experiences, but more relaxed solipsism may include past and possible future experiences.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 9.5)
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
Knowing that a cow is not a horse seems to be a synthetic a priori truth [Dancy,J]
     Full Idea: The fact that a cow is not a horse is a candidate for a priori synthetic truth. It doesn't seem to be analytic, because you can know what a cow is without knowing what a horse is.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 14.3)
12. Knowledge Sources / B. Perception / 1. Perception
Perception is either direct realism, indirect realism, or phenomenalism [Dancy,J]
     Full Idea: There are three main families of theories of perception: direct realism, indirect realism, and phenomenalism.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.2)
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / e. Primary/secondary critique
We can't grasp the separation of quality types, or what a primary-quality world would be like [Dancy,J]
     Full Idea: There is doubt about whether our experience of the world is such that we can conceive of the sort of separation of primary and secondary qualities which the scientific view calls for, and can understand what the world is like with no secondary qualities.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.3)
     A reaction: Dancy attributes these doubts to Berkeley (e.g. Idea 3837). I think what is claimed here is false. Obviously we spend our whole lives immersed in secondary qualities, but separating the different aspects is precisely what scientists (and philosophers) do.
For direct realists the secondary and primary qualities seem equally direct [Dancy,J]
     Full Idea: For a direct realist our awareness of colour and heat can hardly be of a different order from our awareness of shape and size. Both sorts of properties are presented with equal directness.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.3)
     A reaction: This is a good objection to 'direct scientific realism', which claims direct apprehension of primary qualities alongside a totally relative view of secondary qualities. The best response seems to be to move to a representative view of primary properties.
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
We can be looking at distant stars which no longer actually exist [Dancy,J]
     Full Idea: An object such as a distant star can have ceased to exist by the moment at which we are directly aware of it.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.2)
12. Knowledge Sources / B. Perception / 4. Sense Data / b. Nature of sense-data
It is not clear from the nature of sense data whether we should accept them as facts [Dancy,J]
     Full Idea: The question whether something which appears as datum should remain as accepted fact is one which is not even partially determined by its origin as datum.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.5)
12. Knowledge Sources / B. Perception / 7. Causal Perception
Appearances don't guarantee reality, unless the appearance is actually caused by the reality [Dancy,J]
     Full Idea: If I stare at a white wall with my brain wired to a virtual reality computer, and it generates a white wall, we wouldn't say I am seeing reality. It seems that the wall itself must in some way cause my perception of it.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 11.4)
     A reaction: But suppose the computer generated in my mind an image of the wall which was actually in front of me? And suppose the computer got its image from the identical wall next door, not from mine? And it was only judged identical because the architect said so
Perceptual beliefs may be directly caused, but generalisations can't be [Dancy,J]
     Full Idea: A perceptual belief that p can have as its main cause the fact that p. More general facts (all men are mortal; e=mc2) cannot be the main cause of my belief, even if they do function causally in some way.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 11.5)
     A reaction: Note that the perceptual belief can be the "main" cause; it seems to me that most beliefs are caused by judgements, though I may normally accept beliefs which are directly caused by perception, if I have no reason to challenge them.
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
If perception and memory are indirect, then two things stand between mind and reality [Dancy,J]
     Full Idea: If perception is indirect as well as memory, this means there are two direct objects of awareness between the remembering mind and the original object.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 12.2)
Memories aren't directly about the past, because time-lags and illusions suggest representation [Dancy,J]
     Full Idea: Direct realism about memory believes the memory is the past. But the time-lag argument and various illusions are powerful here, suggesting indirect realism involving a memory image.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 12.2)
Phenomenalism about memory denies the past, or reduces it to present experience [Dancy,J]
     Full Idea: Eliminative phenomenalism about memory holds that there is no such thing as the past, just certain present experiences; reductive phenomenalism holds that there is a past, but it is no more than a complex of those present experiences.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 12.4)
I can remember plans about the future, and images aren't essential (2+3=5) [Dancy,J]
     Full Idea: Memory is not solely concerned with the past, let alone one's own past (I remember that I must be in London next week), and need not involve images (2+2=4).
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 12.3)
     A reaction: I can hardly remember the future, so I presume I am remembering my past commitment to go to London, even if I visualise the future with me in London. The non-necessity of images seems right. I can remember the Mona Lisa without a precise image.
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / a. Agrippa's trilemma
Foundations are justified by non-beliefs, or circularly, or they need no justification [Dancy,J]
     Full Idea: Foundationalism can get rid of the regress argument with one of three types of belief: those justified by something other than beliefs, those which justify themselves, or those which need no justification.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.3)
     A reaction: A nice clear trilemma, and none of them will do, which is why foundationalism is false. I vote for Davidson's view, that only a belief can justify another belief.
13. Knowledge Criteria / A. Justification Problems / 3. Internal or External / a. Pro-internalism
For internalists we must actually know that the fact caused the belief [Dancy,J]
     Full Idea: The internalist would claim that even if the belief is caused by the true fact to which it refers, it is also necessary that the believer believes that this is how their belief arose, and not some other way.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 3.5)
     A reaction: I'm converted to internalism. If the belief is externally supported in the right way, then it may well be a true belief, but knowledge needs critical faculties, and justifications which can be articulated.
Internalists tend to favour coherent justification, but not the coherence theory of truth [Dancy,J]
     Full Idea: Internalists such as Keith Lehrer tend to suggest that we adopt a coherence theory of justification but reject the coherence theory of truth.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.3)
     A reaction: I agree with Lehrer. Truth just isn't coherence, for all sorts of well known reasons (found in this database!). High coherence can be totally false. For justification, though, it is the best we have.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
Foundationalism requires inferential and non-inferential justification [Dancy,J]
     Full Idea: The core of any form of foundationalism is the view that there are two forms of justification - inferential and non-inferential - and that non-inferential justification must be possible to avoid a sceptical regress.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.1)
     A reaction: The foundation may be non-inferential, but is it also non-evidential, or devoid of any support at all, apart from its own eloquent self? I can't buy that, I'm afraid.
Foundationalists must accept not only the basic beliefs, but also rules of inference for further progress [Dancy,J]
     Full Idea: Foundationalists suppose we need not only basic beliefs, but also principles of inference to move to the more sophisticated superstructure. We may understand what justifies the basic beliefs, but what about the inference principles?
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.3)
     A reaction: Very nice question. Of course, you can't justify everything, but each part of a system can be scrutinised in turn by the other parts (with scrutinising principles tested pragmatically).
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
If basic beliefs can be false, falsehood in non-basic beliefs might by a symptom [Dancy,J]
     Full Idea: Falsehood in a non-basic belief would be a reason to doubt the basic beliefs which support it, once we have admitted that basic beliefs can be false.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.3)
     A reaction: The yearning for foundations arises from the yearning for certainty. If one embraces the fallibilist view of knowledge, as I do, then there is little motivation for foundationalism.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Beliefs can only be infallible by having almost no content [Dancy,J]
     Full Idea: Infallible beliefs must have vanishingly small content. No belief with enough content to support the superstructure in which we are really interested is going to be infallible.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.2)
     A reaction: I see no reason why a foundationalist should not be a fallibilist, rather than insisting on the infallibility of their basic beliefs. I don't, though, see how basic beliefs can count as knowledge.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Coherentism gives a possible justification of induction, and opposes scepticism [Dancy,J]
     Full Idea: Coherentists feel that their approach provides a possible justification for induction, and offers a general stance from which the sceptic can be defused, if not rebutted.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.3)
     A reaction: These are two good reasons why I vote for coherentism (about justification, NOT about truth). Coherence is the main tool for leading us to the best explanation.
Idealists must be coherentists, but coherentists needn't be idealists [Dancy,J]
     Full Idea: An idealist should perhaps be a coherentist, but there seems to be no reason why the coherentist should be an idealist; the link between the two is all one-way.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 9.5)
     A reaction: I don't see why an idealist shouldn't be a rationalist foundationalist, with a private reality full of certainties founded on simple a priori truths. Personally I'm an empiricist coherentist, this week.
For coherentists justification and truth are not radically different things [Dancy,J]
     Full Idea: The coherentist idea is that justification and truth are not properties of radically different types.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 11.6)
     A reaction: Oh. And I thought I was a coherentist. It take it that keeping coherence for foundations separate from coherence as truth is absolutely basic. The latter is nonsense.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
If it is empirical propositions which have to be coherent, this eliminates coherent fiction [Dancy,J]
     Full Idea: If coherence is grounded in, and is trying to make sense of, a set of empirical propositions, this will eliminate some of the more fanciful sets of coherent propositions, such as the complete Sherlock Holmes stories.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.2)
     A reaction: Interestingly, I suspect that embracing the coherence view of justification drives one back to empiricisim (pace Bonjour), because that is the most authoritative part of the pattern of beliefs.
13. Knowledge Criteria / C. External Justification / 1. External Justification
Externalism could even make belief unnecessary (e.g. in animals) [Dancy,J]
     Full Idea: One reading of the externalist approach may lead to a rejection of the belief condition for knowledge (in animals, perhaps).
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 9.3)
     A reaction: At this point the concept of 'knowledge' seems to disperse into the mist. This pushes me to a 'setting the bar high' view of knowledge. Otherwise plants will have it, and we don't want that.
13. Knowledge Criteria / C. External Justification / 2. Causal Justification
How can a causal theory of justification show that all men die? [Dancy,J]
     Full Idea: How can a causal analysis of justification show that I know that all men die?
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 2.3)
     A reaction: I presume he means that inductive generalisations can't be purely causal. The claim that men are immortal is absurd because it is 'unconnected' to what actually happens.
Causal theories don't allow for errors in justification [Dancy,J]
     Full Idea: Causal accounts of justification do not allow for the possibility that a false belief may still be justified.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 2.4)
     A reaction: Good. If you switch to what you only think is the cause of your belief, you have gone internalist and ruined the party. You can't deny that a falsehood can be justified, or justification is vacuous.
13. Knowledge Criteria / C. External Justification / 8. Social Justification
Coherentism moves us towards a more social, shared view of knowledge [Dancy,J]
     Full Idea: An advantage of coherentism is that it directs attention away from the individual's struggle to achieve knowledge (the classical conception), and points to knowledge as a social phenomenon, shared, and increased by means of sharing.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 8.3)
     A reaction: This is exactly the view which I now embrace. Internal coherence is the basis, but that spills out into the community, and into books, and into the relativity of social acceptance.
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
What is the point of arguing against knowledge, if being right undermines your own argument? [Dancy,J]
     Full Idea: What is the point of arguing that justified belief is impossible, for if you were right there could be no reasons for your conclusion?
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 1.3)
14. Science / C. Induction / 6. Bayes's Theorem
Probabilities can only be assessed relative to some evidence [Dancy,J]
     Full Idea: In Probability Calculus probability is only assessed relative to some evidence.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 4.1)
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / d. Other minds by analogy
The argument from analogy rests on one instance alone [Dancy,J]
     Full Idea: As an inductive argument Mill's argument from analogy (other people have inputs and outputs like mine, so the intermediate explanation must be the same) is weak because it is based on a single instance.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 5.3)
     A reaction: The argument may be 'weak' as a piece of pure logic, but when faced with a strange situation, one's own case seems like crucial evidence, like a single eye-witness to a crime.
You can't separate mind and behaviour, as the analogy argument attempts [Dancy,J]
     Full Idea: The analogy argument makes the error (as Wittgenstein showed) of assuming that mind is quite separate from behaviour, and yet I can understand what it is for others to have mental states, which is contradictory.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 5.3)
     A reaction: It has always seemed to me that Wittgenstein is excessively behaviourist, and he always seems to be flirting with eliminative views of mind, so he was never bothered about other minds. Minds aren't separate from behaviour, but they are distinct.
19. Language / A. Nature of Meaning / 5. Meaning as Verification
Verificationism (the 'verification principle') is an earlier form of anti-realism [Dancy,J]
     Full Idea: Verificationism (the 'verification principle') is an earlier form of anti-realism.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 1.note)
     A reaction: If the one true God announced that there is a real world out there, I might take that as a verification of the fact.
Logical positivism implies foundationalism, by dividing weak from strong verifications [Dancy,J]
     Full Idea: The foundationalist claim that there are inferential and non-inferential justifications is mirrored by the claim of logical empiricism (the verification principle) that all significant statements are either strongly or weakly verifiable.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 6.2)
     A reaction: I take it to be characteristic of both to divide the support for something into two types, one of which is basic, and the other built up on the basics. The first step is to decide what is basic.
19. Language / A. Nature of Meaning / 7. Meaning Holism / b. Language holism
If the meanings of sentences depend on other sentences, how did we learn language? [Dancy,J]
     Full Idea: It is clearly possible to learn a language from scratch, because we have all done it, but if holism is true and the meaning of each sentence depends on the meanings of others, how did we do it?
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 7.2)
     A reaction: The question of 'how did it ever get started?' actually seems to block almost every explanation of everything that ever happens. How do I begin to move my hand?
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
There is an indeterminacy in juggling apparent meanings against probable beliefs [Dancy,J]
     Full Idea: Indeterminacy stems from an interplay between belief and meaning, as with a man who tells you he keeps two rhinoceri in the fridge and squeezes the juice of one for a drink each morning.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 7.4)
     A reaction: I don't understand why an 'interplay' is called an 'indeterminacy'. Typical philosophers. Close examination will usually show whether the change is just in belief, or just in meaning, or in both.
19. Language / F. Communication / 6. Interpreting Language / c. Principle of charity
Charity makes native beliefs largely true, and Humanity makes them similar to ours [Dancy,J]
     Full Idea: One criterion for successful translation is that it show native beliefs to be largely true (Principle of Charity), and another is that it imputes to natives beliefs we can make sense of them having (Principle of Humanity).
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 7.4)
     A reaction: The trouble with such guidelines is that they always have to be 'all things being equal'. Sometimes the natives are really idiotic, and sometimes their attitudes seem quite inhuman.
21. Aesthetics / A. Aesthetic Experience / 3. Taste
Taste is the capacity to judge an object or representation which is thought to be beautiful [Tarski, by Schellekens]
     Full Idea: Taste is the faculty for judging an object or a kind of representation through a satisfaction or a dissatisfaction, ...where the object of such a satisfaction is called beautiful.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Elizabeth Schellekens - Immanuel Kant (aesthetics) 1
     A reaction: We usually avoid the word 'faculty' nowadays, because it implies a specific mechanism, but 'capacity' will do. Kant is said to focus specifically on beauty, whereas modern aestheticians have a broader view of the type of subject matter.
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
     Full Idea: Archelaus was the first person to say that the universe is boundless.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]
     Full Idea: Archelaus wrote that life on Earth began in a primeval slime.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus
     A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea.