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All the ideas for 'Two Problems of Epistemology', 'The Tarskian Turn' and 'Principles of Philosophy of the Future'

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71 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Philosophy is the most general intellectual discipline [Horsten]
     Full Idea: Philosophy is the most general intellectual discipline.
     From: Leon Horsten (The Tarskian Turn [2011], 05.1)
     A reaction: Very simple, but exactly how I see the subject. It is continuous with the sciences, and tries to give an account of nature, but operating at an extreme level of generality. It must respect the findings of science, but offer bold interpretations.
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / b. Philosophy as transcendent
Only that which can be an object of religion is an object of philosophy [Feuerbach]
     Full Idea: Only that which can be an object of religion is an object of philosophy.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §35)
     A reaction: The temple of Pythagoras at Solon sounds like an embodiment of this idea. The obvious candidate would be truth, to which philosophers must show almost religious respect. Some what motivates the philosophy of a minimalist (Idea 3750)?
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Philosophy should not focus on names, but on the determined nature of things [Feuerbach]
     Full Idea: Philosophy need not care about the conceptions that common usage or misuse attaches to a name; philosophy, however, has to bind itself to the determined nature of things, whose signs are names.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §23)
     A reaction: I like this attempt to nip ordinary language philosophy in the bud. Indeed I like the notion of philosophy binding itself to the 'determined nature of things' (which sound like essences to me), rather than to their names or descriptions.
1. Philosophy / H. Continental Philosophy / 1. Continental Philosophy
Modern philosophy begins with Descartes' abstraction from sensation and matter [Feuerbach]
     Full Idea: The beginning of Descartes' philosophy, namely, the abstraction from sensation and matter, is the beginning of modern speculative philosophy.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §10)
     A reaction: In Britain it might be said that modern philosophy begins with a rebellion against Descartes' move. Feuerbach is charting the movement towards idealism.
Empiricism is right about ideas, but forgets man himself as one of our objects [Feuerbach]
     Full Idea: Empiricism rightly derives the origin of our ideas from the senses; only it forgets that the most important and essential object of man is man himself.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §41)
     A reaction: This seems to nicely pinpoint the objection of most 'continental' philosophy to British empiricism and analytic philosophy. It seems to point towards Husserl's phenomenology as the next step. It is true that empiricists divided person from world.
2. Reason / B. Laws of Thought / 1. Laws of Thought
The laws of reality are also the laws of thought [Feuerbach]
     Full Idea: The laws of reality are also the laws of thought.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §45)
     A reaction: I like this a lot, though it runs contrary to a lot of conventionalist thinking in the twentieth century. Russell, though, agrees with Feuerbach (Idea 5405). There is not much point to thought if it doesn't plug into reality at the roots.
2. Reason / D. Definition / 2. Aims of Definition
A definition should allow the defined term to be eliminated [Horsten]
     Full Idea: A definition allows a defined term to be eliminated in every context in which it appears.
     From: Leon Horsten (The Tarskian Turn [2011], 04.2)
     A reaction: To do that, a definition had better be incredibly comprehensive, so that no nice nuance of the original term is thrown out.
3. Truth / A. Truth Problems / 1. Truth
Truth is a property, because the truth predicate has an extension [Horsten]
     Full Idea: I take truth to be a property because the truth predicate has an extension - the collection of all true sentences - and this collection does not (unlike the 'extension' of 'exists') consist of everything, or even of all sentences.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
     A reaction: He concedes that it may be an 'uninteresting' property. My problem is always that I am unconvinced that truth is tied to sentences. I can make perfect sense of animal thoughts being right or wrong. Extension of mental propositions?
Semantic theories of truth seek models; axiomatic (syntactic) theories seek logical principles [Horsten]
     Full Idea: There are semantical theories of truth, concerned with models for languages containing the truth predicate, and axiomatic (or syntactic) theories, interested in basic logical principles governing the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
     A reaction: This is the map of contemporary debates, which seem now to have given up talking about 'correspondence', 'coherence' etc.
3. Truth / A. Truth Problems / 2. Defining Truth
Truth has no 'nature', but we should try to describe its behaviour in inferences [Horsten]
     Full Idea: We should not aim at describing the nature of truth because there is no such thing. Rather, we should aim at describing the inferential behaviour of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 10.2.3)
3. Truth / A. Truth Problems / 5. Truth Bearers
Propositions have sentence-like structures, so it matters little which bears the truth [Horsten]
     Full Idea: It makes little difference, at least in extensional contexts, whether the truth bearers are propositions or sentences (or assertions). Even if the bearers are propositions rather than sentences, propositions are structured rather like sentences.
     From: Leon Horsten (The Tarskian Turn [2011], 02.4)
     A reaction: The 'extensional' context means you are only talking about the things that are referred to, and not about the way this is expressed. I prefer propositions, but this is an interesting point.
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Modern correspondence is said to be with the facts, not with true propositions [Horsten]
     Full Idea: Modern correspondence theorists no longer take things to correspond to true propositions; they consider facts to be the truthmakers of propositions.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: If we then define facts as the way certain things are, independently from our thinking about it, at least we seem to be avoiding circularity. Not much point in correspondence accounts if you are not a robust realist (like me). [14,000th idea, 23/4/12!]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
The correspondence 'theory' is too vague - about both 'correspondence' and 'facts' [Horsten]
     Full Idea: The principle difficulty of the correspondence theory of truth is its vagueness. It is too vague to be called a theory until more information is given about what is meant by the terms 'correspondence' and 'fact'. Facts can involve a heavy ontology.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: I see nothing here to make me give up my commitment to the correspondence view of truth, though it sounds as if I will have to give up the word 'theory' in that context. Truth is so obviously about thought fitting reality that there is nothing to discuss.
3. Truth / D. Coherence Truth / 2. Coherence Truth Critique
The coherence theory allows multiple coherent wholes, which could contradict one another [Horsten]
     Full Idea: The coherence theory seems too liberal. It seems there can be more than one systematic whole which, while being internally coherent, contradict each other, and thus cannot all be true. Coherence is a necessary but not sufficient condition for truth.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: This is a modern post-Tarski axiomatic truth theorist making very short work indeed of the coherence theory of truth. I take Horsten to be correct.
3. Truth / E. Pragmatic Truth / 1. Pragmatic Truth
The pragmatic theory of truth is relative; useful for group A can be useless for group B [Horsten]
     Full Idea: The pragmatic theory is unsatisfactory because usefulness is a relative notion. One theory can be useful to group A while being thoroughly impractical for group B. This would make the theory both truth and false.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: This objection, along with the obvious fact that certain falsehoods can be very useful, would seem to rule pragmatism out as a theory of truth. It is, in fact, an abandonment of truth.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Tarski's hierarchy lacks uniform truth, and depends on contingent factors [Horsten]
     Full Idea: According to the Tarskian hierarchical conception, truth is not a uniform notion. ...Also Kripke has emphasised that the level of a token of the truth predicate can depend on contingent factors, such as what else has been said by a speaker.
     From: Leon Horsten (The Tarskian Turn [2011], 04.5)
Tarski Bi-conditional: if you'll assert φ you'll assert φ-is-true - and also vice versa [Horsten]
     Full Idea: The axiom schema 'Sentence "phi;" is true iff φ' is the (unrestricted) Tarski-Biconditional, and is motivated by the thought that if you are willing to assume or outright assert that φ, you will assert that φ is true - and also vice versa.
     From: Leon Horsten (The Tarskian Turn [2011], 02.2)
     A reaction: Very helpful! Most people are just bewildered by the Tarski bi-conditional ('"Snow is white"...), but this formulation nicely shows its minimal character while showing that it really does say something. It says what truths and truth-claims commit you to.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
Semantic theories have a regress problem in describing truth in the languages for the models [Horsten]
     Full Idea: Semantic theories give a class of models with a truth predicate, ...but Tarski taught us that this needs a more encompassing framework than its language...so how is the semantics of the framework expressed? The model route has a regress.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
     A reaction: [compressed] So this regress problem, of endless theories of truth going up the hierarchy, is Horsten's main reason for opting for axiomatic theories, which he then tries to strengthen, so that they are not quite so deflated.
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
'Reflexive' truth theories allow iterations (it is T that it is T that p) [Horsten]
     Full Idea: A theory of truth is 'reflexive' if it allows us to prove truth-iterations ("It is true that it is true that so-and-so").
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
Axiomatic approaches to truth avoid the regress problem of semantic theories [Horsten]
     Full Idea: The axiomatic approach to truth does not suffer from the regress problem.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
     A reaction: See Idea 15345 for the regress problem. The difficulty then seems to be that axiomatic approaches lack expressive power, so the hunt is on for a set of axioms which will do a decent job. Fun work, if you can cope with it.
A good theory of truth must be compositional (as well as deriving biconditionals) [Horsten]
     Full Idea: Deriving many Tarski-biconditionals is not a sufficient condition for being a good theory of truth. A good theory of truth must in addition do justice to the compositional nature of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 06.1)
An axiomatic theory needs to be of maximal strength, while being natural and sound [Horsten]
     Full Idea: The challenge is to find the arithmetically strongest axiomatical truth theory that is both natural and truth-theoretically sound.
     From: Leon Horsten (The Tarskian Turn [2011], 07.7)
The Naďve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten]
     Full Idea: The Naďve Theory of Truth collects all the Tarski bi-conditionals of a language and takes them as axioms. But no consistent theory extending Peano arithmetic can prove all of them. It is inconsistent, and even formalises the liar paradox.
     From: Leon Horsten (The Tarskian Turn [2011], 03.5.2)
     A reaction: [compressed] This looks to me like the account of truth that Davidson was working with, since he just seemed to be compiling bi-conditionals for tricky cases. (Wrong! He championed the Compositional Theory, Horsten p.71)
Axiomatic theories take truth as primitive, and propose some laws of truth as axioms [Horsten]
     Full Idea: In the axiomatic approach we take the truth predicate to express an irreducible, primitive notion. The meaning of the truth predicate is partially explicated by proposing certain laws of truth as basic principles, as axioms.
     From: Leon Horsten (The Tarskian Turn [2011], 04.2)
     A reaction: Judging by Horsten's book, this is a rather fruitful line of enquiry, but it still seems like a bit of a defeat to take truth as 'primitive'. Presumably you could add some vague notion of correspondence as the background picture.
By adding truth to Peano Arithmetic we increase its power, so truth has mathematical content! [Horsten]
     Full Idea: It is surprising that just by adding to Peano Arithmetic principles concerning the notion of truth, we increase the mathematical strength of PA. So, contrary to expectations, the 'philosophical' notion of truth has real mathematical content.
     From: Leon Horsten (The Tarskian Turn [2011], 06.4)
     A reaction: Horsten invites us to be really boggled by this. All of this is in the Compositional Theory TC. It enables a proof of the consistency of arithmetic (but still won't escape Gödel's Second).
Axiomatic approaches avoid limiting definitions to avoid the truth predicate, and limited sizes of models [Horsten]
     Full Idea: An adequate definition of truth can only be given for the fragment of our language that does not contain the truth predicate. A model can never encompass the whole of the domain of discourse of our language. The axiomatic approach avoids these problems.
     From: Leon Horsten (The Tarskian Turn [2011], 10.1)
3. Truth / G. Axiomatic Truth / 2. FS Truth Axioms
Friedman-Sheard theory keeps classical logic and aims for maximum strength [Horsten]
     Full Idea: The Friedman-Sheard theory of truth holds onto classical logic and tries to construct a theory that is as strong as possible.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
3. Truth / G. Axiomatic Truth / 3. KF Truth Axioms
Kripke-Feferman has truth gaps, instead of classical logic, and aims for maximum strength [Horsten]
     Full Idea: If we abandon classical logic in favour of truth-value gaps and try to strengthen the theory, this leads to the Kripke-Feferman theory of truth, and variants of it.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Inferential deflationism says truth has no essence because no unrestricted logic governs the concept [Horsten]
     Full Idea: According to 'inferential deflationism', truth is a concept without a nature or an essence. This is betrayed by the fact that there are no unrestricted logical laws that govern the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
Deflationism concerns the nature and role of truth, but not its laws [Horsten]
     Full Idea: Deflationism is not a theory of the laws of truth. It is a view on the nature and role of the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05 Intro)
Deflationism skips definitions and models, and offers just accounts of basic laws of truth [Horsten]
     Full Idea: Contemporary deflationism about truth does not attempt to define truth, and does not rely on models containing the truth predicate. Instead they are interpretations of axiomatic theories of truth, containing only basic laws of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
This deflationary account says truth has a role in generality, and in inference [Horsten]
     Full Idea: On the conception of deflationism developed in this book, the prime positive role of the truth predicate is to serve as a device for expressing generalities, and an inferential tool.
     From: Leon Horsten (The Tarskian Turn [2011], 07.5)
Deflationism says truth isn't a topic on its own - it just concerns what is true [Horsten]
     Full Idea: Deflationism says the theory of truth does not have a substantial domain of its own. The domain of the theory of truth consists of the bearers of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05.1)
     A reaction: The immediate thought is that truth also concerns falsehoods, which would be inexplicable without it. If physics just concerns the physical, does that mean that physics lacks its own 'domain'? Generalising about the truths is a topic.
Deflation: instead of asserting a sentence, we can treat it as an object with the truth-property [Horsten]
     Full Idea: The Deflationary view just says that instead of asserting a sentence, we can turn the sentence into an object and assert that this object has the property of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05.2.2)
     A reaction: That seems to leave a big question hanging, which concerns the nature of the property that is being attributed to this object. Quine 1970:10-13 says it is just a 'device'. Surely you can rest content with that as an account of truth?
4. Formal Logic / E. Nonclassical Logics / 1. Nonclassical Logics
Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten]
     Full Idea: Some nonclassical logic stays close to classical, assuming two mutually exclusive truth values T and F, but some sentences fail to have one. Others have further truth values such as 'half truth', or dialethists allow some T and F at the same time.
     From: Leon Horsten (The Tarskian Turn [2011], 01.2)
     A reaction: I take that to say that the first lot accept bivalence but reject excluded middle (allowing 'truth value gaps'), while the second lot reject both. Bivalence gives the values available, and excluded middle says what has them.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Doubt is thrown on classical logic by the way it so easily produces the liar paradox [Horsten]
     Full Idea: Aside from logic, so little is needed to generate the liar paradox that one wonders whether the laws of classical logic are unrestrictedly valid after all. (Many theories of truth have therefore been formulated in nonclassical logic.)
     From: Leon Horsten (The Tarskian Turn [2011], 01.2)
     A reaction: Kripke uses Strong Kleene logic for his theory. The implication is that debates discussed by Horsten actually have the status of classical logic at stake, as well as the nature of truth.
5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
Deduction Theorem: ψ only derivable from φ iff φ→ψ are axioms [Horsten]
     Full Idea: The Deduction Theorem says ψ is derivable in classical predicate logic from ψ iff the sentence φ→ψ is a theorem of classical logic. Hence inferring φ to ψ is truth-preserving iff the axiom scheme φ→ψ is provable.
     From: Leon Horsten (The Tarskian Turn [2011], 02.2)
     A reaction: Horsten offers this to show that the Tarski bi-conditionals can themselves be justified, and not just the rule of inference involved. Apparently you can only derive something if you first announce that you have the ability to derive it. Odd.
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
A theory is 'non-conservative' if it facilitates new mathematical proofs [Horsten]
     Full Idea: A theory is 'non-conservative' if it allows us to prove mathematical facts that go beyond what the background mathematical theory can prove on its own.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
     A reaction: This is an instance of the relationship with mathematics being used as the test case for explorations of logic. It is a standard research method, because it is so precise, but should not be mistaken for the last word about a theory.
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
It is easier to imagine truth-value gaps (for the Liar, say) than for truth-value gluts (both T and F) [Horsten]
     Full Idea: It is easier to imagine what it is like for a sentence to lack a truth value than what it is like for a sentence to be both truth and false. So I am grudgingly willing to entertain the possibility that certain sentences (like the Liar) lack a truth value.
     From: Leon Horsten (The Tarskian Turn [2011], 02.5)
     A reaction: Fans of truth value gluts are dialethists like Graham Priest. I'm with Horsten on this one. But in what way can a sentence be meaningful if it lacks a truth-value? He mentions unfulfilled presuppositions and indicative conditionals as gappy.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
Satisfaction is a primitive notion, and very liable to semantical paradoxes [Horsten]
     Full Idea: Satisfaction is a more primitive notion than truth, and it is even more susceptible to semantical paradoxes than the truth predicate.
     From: Leon Horsten (The Tarskian Turn [2011], 06.3)
     A reaction: The Liar is the best known paradox here. Tarski bases his account of truth on this primitive notion, so Horsten is pointing out the difficulties.
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
The first incompleteness theorem means that consistency does not entail soundness [Horsten]
     Full Idea: It is a lesson of the first incompleteness theorem that consistency does not entail soundness. If we add the negation of the gödel sentence for PA as an extra axiom to PA, the result is consistent. This negation is false, so the theory is unsound.
     From: Leon Horsten (The Tarskian Turn [2011], 04.3)
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Strengthened Liar: 'this sentence is not true in any context' - in no context can this be evaluated [Horsten]
     Full Idea: The Strengthened Liar sentence says 'this sentence is not true in any context'. It is not hard to figure out that there is no context in which the sentence can be coherently evaluated.
     From: Leon Horsten (The Tarskian Turn [2011], 04.6)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten]
     Full Idea: The number of English expressions is denumerably infinite. But Cantor's theorem can be used to show that there are nondenumerably many real numbers. So not every real number has a (simple or complex name in English).
     From: Leon Horsten (The Tarskian Turn [2011], 06.3)
     A reaction: This really bothers me. Are we supposed to be committed to the existence of entities which are beyond our powers of naming? How precise must naming be? If I say 'pick a random real number', might that potentially name all of them?
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
ZFC showed that the concept of set is mathematical, not logical, because of its existence claims [Horsten]
     Full Idea: One of the strengths of ZFC is that it shows that the concept of set is a mathematical concept. Many originally took it to be a logical concept. But ZFC makes mind-boggling existence claims, which should not follow if it was a logical concept.
     From: Leon Horsten (The Tarskian Turn [2011], 05.2.3)
     A reaction: This suggests that set theory is not just a way of expressing mathematics (see Benacerraf 1965), but that some aspect of mathematics has been revealed by it - maybe even its essential nature.
Set theory is substantial over first-order arithmetic, because it enables new proofs [Horsten]
     Full Idea: The nonconservativeness of set theory over first-order arithmetic has done much to establish set theory as a substantial theory indeed.
     From: Leon Horsten (The Tarskian Turn [2011], 07.5)
     A reaction: Horsten goes on to point out the price paid, which is the whole new ontology which has to be added to the arithmetic. Who cares? It's all fictions anyway!
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
Predicativism says mathematical definitions must not include the thing being defined [Horsten]
     Full Idea: Predicativism has it that a mathematical object (such as a set of numbers) cannot be defined by quantifying over a collection that includes that same mathematical object. To do so would be a violation of the vicious circle principle.
     From: Leon Horsten (The Tarskian Turn [2011], 07.7)
     A reaction: In other words, when you define an object you are obliged to predicate something new, and not just recycle the stuff you already have.
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
Absolute thought remains in another world from being [Feuerbach]
     Full Idea: Absolute thought never extricates itself from itself to become being. Being remains in another world. …If being is to be added to an object of thought, so must something distinct from thought be added to thought itself.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §24/5)
     A reaction: This sounds a bit like a child wishing for the moon. Is he saying he doesn't just want to think about reality - he wants his mental states to BE external reality? The distinction between a thought and its content or intentionality would help here.
Being is what is undetermined, and hence indistinguishable [Feuerbach]
     Full Idea: Being in the sense in which it is an object of speculative thought is that which is purely and simply unmediated, that is, undetermined; in other words, there is nothing to distinguish and nothing to think of in being.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], 26)
     A reaction: This sounds remarkably like the idea of 'prime matter' used in scholastic Aristotelian philosophy. Matter existing without form is somehow ungraspable, but presented from Hegel onwards as the ultimate mystery.
7. Existence / A. Nature of Existence / 3. Being / f. Primary being
Being posits essence, and my essence is my being [Feuerbach]
     Full Idea: Being is the positing of essence. That which is my essence is my being. The fish exists in water; you cannot, however, separate its essence from this being.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §27)
     A reaction: This throws a different light on later (e.g. Heidegger) discussions of 'being', which may map onto Aristotelian discussions of essences.
7. Existence / A. Nature of Existence / 3. Being / g. Particular being
Particularity belongs to being, whereas generality belongs to thought [Feuerbach]
     Full Idea: Particularity and individuality belong to being, whereas generality belongs to thought.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §29)
     A reaction: This agrees with Russell's view that every sentence (and proposition) must contain a universal (i.e a generality). The very notion of thinking 'about' a horse seems to require a move to the universal concept of a horse.
7. Existence / A. Nature of Existence / 3. Being / h. Dasein (being human)
The only true being is of the senses, perception, feeling and love [Feuerbach]
     Full Idea: Being as an object of being - and only this being is being and deserves the name of being - is the being of the senses, perception, feeling, and love. …Only passion is the hallmark of existence.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §33)
     A reaction: This remark seems to make Feuerbach a romantic and anti-Enlightenment figure. I don't see why there shouldn't be just as much 'being' in doing maths as in admiring a landscape. The mention of love links him to Empedocles (Ideas 459 + 630).
7. Existence / D. Theories of Reality / 8. Facts / b. Types of fact
We may believe in atomic facts, but surely not complex disjunctive ones? [Horsten]
     Full Idea: While positive and perhaps even negative atomic facts may be unproblematic, it seems excessive to commit oneself to the existence of logically complex facts such as disjunctive facts.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: Presumably it is hard to deny that very complex statements involving massive disjunctions can be true or false. But why does commitment to real facts have to involve a huge ontology? The ontology is just the ingredients of the fact, isn't it?
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
In the supervaluationist account, disjunctions are not determined by their disjuncts [Horsten]
     Full Idea: If 'Britain is large' and 'Italy is large' lack truth values, then so must 'Britain or Italy is large' - so on the supervaluationist account the truth value of a disjunction is not determined by the truth values of its disjuncts.
     From: Leon Horsten (The Tarskian Turn [2011], 06.2)
     A reaction: Compare Idea 15362 to get the full picture here.
If 'Italy is large' lacks truth, so must 'Italy is not large'; but classical logic says it's large or it isn't [Horsten]
     Full Idea: If 'Italy is a large country' lacks a truth value, then so too, presumably, does 'Italy is not a large country'. But 'Italy is or is not a large country' is true, on the supervaluationist account, because it is a truth of classical propositional logic.
     From: Leon Horsten (The Tarskian Turn [2011], 06.2)
     A reaction: See also Idea 15363. He cites Fine 1975.
11. Knowledge Aims / A. Knowledge / 4. Belief / c. Aim of beliefs
Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten]
     Full Idea: In the debate about doxastic attitudes towards indicative conditional sentences, one finds philosophers who claim that conditionals can be believed even though they have no truth value (and thus are not true).
     From: Leon Horsten (The Tarskian Turn [2011], 09.3)
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / b. Transcendental idealism
Consciousness is absolute reality, and everything exists through consciousness [Feuerbach]
     Full Idea: Consciousness is the absolute reality, the measure of all existence; all that exists, exists only as being for consciousness, as comprehended in consciousness; for consciousness is first and foremost being.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §17)
     A reaction: This is Feuerbach declaring himself in favour of idealism even as he was trying to rebel against it, and move towards a more sensuous and human view of the world. I just see idealists as confusing ontology and epistemology.
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
Ideas arise through communication, and reason is reached through community [Feuerbach]
     Full Idea: Only through communication and conversation between man and man do ideas arise; not alone, but only with others, does one reach notions and reason in general.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §41)
     A reaction: This is a strikingly modern view of the solipsism problem, and is close in spirit to Wittgenstein's Private Language Argument (Ideas 4143 +4158). Feuerbach is interested in universals rather than rules. I prefer Feuerbach.
12. Knowledge Sources / B. Perception / 6. Inference in Perception
In man the lowest senses of smell and taste elevate themselves to intellectual acts [Feuerbach]
     Full Idea: Even the lowest senses, smell and taste, elevate themselves in man to intellectual and scientific acts.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §53)
     A reaction: Since Darwin we have, I am glad to say, lost this need to distinguish what is 'low' or 'high', and to try to show that even our 'lowest' functions are on the 'high' side. Personally, though, I still need the low/high distinction in moral thinking.
14. Science / A. Basis of Science / 6. Falsification
Particulars can be verified or falsified, but general statements can only be falsified (conclusively) [Popper]
     Full Idea: Whereas particular reality statements are in principle completely verifiable or falsifiable, things are different for general reality statements: they can indeed be conclusively falsified, they can acquire a negative truth value, but not a positive one.
     From: Karl Popper (Two Problems of Epistemology [1932], p.256), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 18 'Laws'
     A reaction: This sounds like a logician's approach to science, but I prefer to look at coherence, where very little is actually conclusive, and one tinkers with the theory instead.
18. Thought / E. Abstraction / 1. Abstract Thought
The new philosophy thinks of the concrete in a concrete (not a abstract) manner [Feuerbach]
     Full Idea: The new philosophy is the philosophy that thinks of the concrete not in an abstract, but in a concrete manner.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §31)
     A reaction: This leads to placing a high value on art, and on virtuous action through particulars rather than principles, and on empirical science. The only problem is that what he proposes is impossible. To think 'about' is to abstract from the particulars.
19. Language / C. Assigning Meanings / 1. Syntax
A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten]
     Full Idea: A notion of formal provability can be articulated in Peano arithmetic. ..This is surprisingly 'linguistic' rather than mathematical, but the key is in the Gödel coding. ..Hence we use Peano arithmetic as a theory of syntax.
     From: Leon Horsten (The Tarskian Turn [2011], 02.4)
     A reaction: This is the explanation of why issues in formal semantics end up being studied in systems based on formal arithmetic. And I had thought it was just because they were geeks who dream in numbers, and can't speak language properly...
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / d. Biological ethics
Plotinus was ashamed to have a body [Feuerbach]
     Full Idea: Plotinus, according to his biographers, was ashamed to have a body.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §29)
     A reaction: When Feuerbach draws our attention to this, we see what an astonishing state it is for a human being to have got into. Modern thought is appalled by it, but it also has something heroic about it, like swimming all the time because you want to be a fish.
22. Metaethics / B. Value / 2. Values / g. Love
If you love nothing, it doesn't matter whether something exists or not [Feuerbach]
     Full Idea: To him who loves nothing it is all the same whether something does or does not exist.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §33)
     A reaction: This seems to me to be quite a good motto for the aim of education - just get them to love something, no matter what (well, almost!). Loving something, even if it is train-spotting, seems a good route to human happiness.
24. Political Theory / A. Basis of a State / 1. A People / a. Human distinctiveness
Man is not a particular being, like animals, but a universal being [Feuerbach]
     Full Idea: Man is not a particular being, like the animals, but a universal being.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §53)
     A reaction: This sounds a bit extravagent. The capacity of man to use universals in thought seems crucial to Feuerbach (though he doesn't directly address the problem). 'We are particulars with access to universals' sounds better.
The essence of man is in community, but with distinct individuals [Feuerbach]
     Full Idea: The essence of man is contained only in the community and unity of man and man; it is a unity, however, which rests only on the reality of the distinction between I and thou.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §59)
     A reaction: In English provincial suburbs (where I live) it is astonishing how little interest in and need for their neighbours people seem to have. People seem to survive without community. Most of us, though, think full human happiness needs community.
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
God's existence cannot be separated from essence and concept, which can only be thought as existing [Feuerbach]
     Full Idea: God is the being in which existence cannot be separated from essence and concept and which cannot be thought except as existing.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §18)
     A reaction: This shows how faith in God endured through the Idealist movement by means of the Ontological Argument, despite the criticisms of Hume and Kant. To me this now appears as an odd abberation in the history of human thought.
28. God / C. Attitudes to God / 4. God Reflects Humanity
If God is only an object for man, then only the essence of man is revealed in God [Feuerbach]
     Full Idea: If God is only an object of man, what is revealed to us in his essence? Nothing but the essence of man.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §07)
     A reaction: It is important to distinguish here between what we could know about God, and what we think God might actually be like. We may well only be able to read the essence of man into God, but we might speculate that God is more than that.
God is what man would like to be [Feuerbach]
     Full Idea: God is what man would like to be.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §29)
     A reaction: It is hard to see how even the most devout person could deny the truth of this. Perhaps the essential hallmark of humanity is a desire to be different from the way we are.
God is for us a mere empty idea, which we fill with our own ego and essence [Feuerbach]
     Full Idea: God exists, but he is for us a tabula rasa, an empty being, a mere idea; God, as we conceive and think of him, is our ego, our mind, and our essence.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §17)
     A reaction: He accepted God's existence because of the Ontological Argument. This is a little stronger than Hume's view (Idea 2185), because Hume seems to be talking about imagining God, but Feuerbach says this is our understanding of God.
29. Religion / B. Monotheistic Religion / 4. Christianity / a. Christianity
Catholicism concerns God in himself, Protestantism what God is for man [Feuerbach]
     Full Idea: Protestantism is no longer concerned, as Catholicism is, about what God is in himself, but about what he is for man.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §02)
     A reaction: It is certainly true that the major religions in their origins seem to be almost exclusively concerned with God alone, and have little interest in human life (or morality).
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
Absolute idealism is the realized divine mind of Leibnizian theism [Feuerbach]
     Full Idea: Absolute idealism is nothing but the realized divine mind of Leibnizian theism.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §10)
     A reaction: In general it seems an accurate commentary that during the eighteenth century philosophers on the continent were designing a religion without God. Kantian duty tries to replace the authority of God with pure reason.