Combining Philosophers

All the ideas for Celsus, Volker Halbach and Arthur Schopenhauer

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147 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophers can't be religious, and don't need to be; philosophy is perilous but free [Schopenhauer]
1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Philosophy considers only the universal, in nature as everywhere else [Schopenhauer]
Everyone is conscious of all philosophical truths, but philosophers bring them to conceptual awareness [Schopenhauer]
1. Philosophy / D. Nature of Philosophy / 8. Humour
Absurdity is incongruity between correct and false points of view [Schopenhauer]
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Metaphysics must understand the world thoroughly, as a principal source of knowledge [Schopenhauer]
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Metaphysics studies the inexplicable ends of explanation [Schopenhauer]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Analysis rests on natural language, but its ideal is a framework which revises language [Halbach]
2. Reason / B. Laws of Thought / 2. Sufficient Reason
Sufficient Reason can't be proved, because all proof presupposes it [Schopenhauer, by Lewis,PB]
'There is nothing without a reason why it should be rather than not be' (a generalisation of 'Why?') [Schopenhauer]
2. Reason / D. Definition / 2. Aims of Definition
An explicit definition enables the elimination of what is defined [Halbach]
2. Reason / E. Argument / 3. Analogy
Don't trust analogies; they are no more than a guideline [Halbach]
3. Truth / A. Truth Problems / 1. Truth
Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach]
Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach]
3. Truth / A. Truth Problems / 2. Defining Truth
Any definition of truth requires a metalanguage [Halbach]
Truth definitions don't produce a good theory, because they go beyond your current language [Halbach]
Traditional definitions of truth often make it more obscure, rather than less [Halbach]
If people have big doubts about truth, a definition might give it more credibility [Halbach]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach]
Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Disquotational truth theories are short of deductive power [Halbach]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach]
CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach]
If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach]
Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [Halbach]
The main semantic theories of truth are Kripke's theory, and revisions semantics [Halbach]
To axiomatise Tarski's truth definition, we need a binary predicate for his 'satisfaction' [Halbach]
Compositional Truth CT has the truth of a sentence depending of the semantic values of its constituents [Halbach]
Gödel numbering means a theory of truth can use Peano Arithmetic as its base theory [Halbach]
Truth axioms need a base theory, because that is where truth issues arise [Halbach]
We know a complete axiomatisation of truth is not feasible [Halbach]
A theory is 'conservative' if it adds no new theorems to its base theory [Halbach, by PG]
The Tarski Biconditional theory TB is Peano Arithmetic, plus truth, plus all Tarski bi-conditionals [Halbach]
Theories of truth are 'typed' (truth can't apply to sentences containing 'true'), or 'type-free' [Halbach]
Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach]
Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach]
3. Truth / G. Axiomatic Truth / 2. FS Truth Axioms
Friedman-Sheard is type-free Compositional Truth, with two inference rules for truth [Halbach]
3. Truth / G. Axiomatic Truth / 3. KF Truth Axioms
Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach]
The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach]
The KF is much stronger deductively than FS, which relies on classical truth [Halbach]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Compositional Truth CT proves generalisations, so is preferred in discussions of deflationism [Halbach]
Some say deflationism is axioms which are conservative over the base theory [Halbach]
Deflationists say truth merely serves to express infinite conjunctions [Halbach]
Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach]
The main problem for deflationists is they can express generalisations, but not prove them [Halbach]
Deflationists say truth is just for expressing infinite conjunctions or generalisations [Halbach]
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach]
In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
To prove the consistency of set theory, we must go beyond set theory [Halbach]
Every attempt at formal rigour uses some set theory [Halbach]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
The underestimated costs of giving up classical logic are found in mathematical reasoning [Halbach]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach]
5. Theory of Logic / E. Structures of Logic / 7. Predicates in Logic
Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach]
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
A theory is some formulae and all of their consequences [Halbach]
5. Theory of Logic / K. Features of Logics / 3. Soundness
You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [Halbach]
Normally we only endorse a theory if we believe it to be sound [Halbach]
Soundness must involve truth; the soundness of PA certainly needs it [Halbach]
5. Theory of Logic / L. Paradox / 1. Paradox
Many new paradoxes may await us when we study interactions between frameworks [Halbach]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The liar paradox applies truth to a negated truth (but the conditional will serve equally) [Halbach]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
The compactness theorem can prove nonstandard models of PA [Halbach]
The global reflection principle seems to express the soundness of Peano Arithmetic [Halbach]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals [Halbach]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
Set theory was liberated early from types, and recent truth-theories are exploring type-free [Halbach]
7. Existence / A. Nature of Existence / 2. Types of Existence
Matter and intellect are inseparable correlatives which only exist relatively, and for each other [Schopenhauer]
7. Existence / C. Structure of Existence / 2. Reduction
That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach]
7. Existence / D. Theories of Reality / 2. Realism
For me the objective thing-in-itself is the will [Schopenhauer]
7. Existence / D. Theories of Reality / 3. Reality
Schopenhauer, unlike other idealists, says reality is irrational [Schopenhauer, by Lewis,PB]
7. Existence / D. Theories of Reality / 4. Anti-realism
The knowing subject and the crude matter of the world are both in themselves unknowable [Schopenhauer]
7. Existence / E. Categories / 1. Categories
No need for a priori categories, since sufficient reason shows the interrelations [Schopenhauer, by Lewis,PB]
10. Modality / A. Necessity / 2. Nature of Necessity
Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach]
10. Modality / A. Necessity / 3. Types of Necessity
Necessity is physical, logical, mathematical or moral [Schopenhauer, by Janaway]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
All necessity arises from causation, which is conditioned; there is no absolute or unconditioned necessity [Schopenhauer]
11. Knowledge Aims / A. Knowledge / 2. Understanding
All understanding is an immediate apprehension of the causal relation [Schopenhauer]
11. Knowledge Aims / A. Knowledge / 3. Value of Knowledge
Knowledge is not power! Ignorant people possess supreme authority [Schopenhauer]
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Descartes found the true beginning of philosophy with the Cogito, in the consciousness of the individual [Schopenhauer]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / a. Idealism
For Schopenhauer, material things would not exist without the mind [Schopenhauer, by Janaway]
Schopenhauer can't use force/energy instead of 'will', because he is not a materialist [Lewis,PB on Schopenhauer]
The world only exists in relation to something else, as an idea of the one who conceives it [Schopenhauer]
We know reality because we know our own bodies and actions [Schopenhauer]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / b. Transcendental idealism
Kant rightly separates appearance and thing-in-itself [Schopenhauer]
Object for a subject and representation are the same thing [Schopenhauer]
12. Knowledge Sources / A. A Priori Knowledge / 1. Nature of the A Priori
A priori propositions are those we could never be seriously motivated to challenge [Schopenhauer]
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
Direct feeling of the senses are merely data; perception of the world comes with understanding causes [Schopenhauer]
12. Knowledge Sources / B. Perception / 5. Interpretation
All perception is intellectual [Schopenhauer]
14. Science / D. Explanation / 1. Explanation / a. Explanation
All knowledge and explanation rests on the inexplicable [Schopenhauer]
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
The four explanations: objects by causes, concepts by ground, maths by spacetime, ethics by motive [Schopenhauer, by Lewis,PB]
15. Nature of Minds / B. Features of Minds / 1. Consciousness / a. Consciousness
A consciousness without an object is no consciousness [Schopenhauer]
15. Nature of Minds / B. Features of Minds / 2. Unconscious Mind
We have hidden and unadmitted desires and fears, suppressed because of vanity [Schopenhauer]
Half our thinking is unconscious, and we reach conclusions while unaware of premises [Schopenhauer]
16. Persons / C. Self-Awareness / 2. Knowing the Self
What we know in ourselves is not a knower but a will [Schopenhauer]
I know both aspects of my body, as representation, and as will [Schopenhauer]
16. Persons / D. Continuity of the Self / 3. Reference of 'I'
The knot of the world is the use of 'I' to refer to both willing and knowing [Schopenhauer]
16. Persons / E. Rejecting the Self / 4. Denial of the Self
It is as perverse to resent our individuality being replaced by others, as to resent the body renewing itself [Schopenhauer]
16. Persons / F. Free Will / 5. Against Free Will
We all regard ourselves a priori as free, but see from experience that character and motive compel us [Schopenhauer]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
We don't control our own thinking [Schopenhauer]
Man's actions are not free, because they follow strictly from impact of motive on character [Schopenhauer]
18. Thought / D. Concepts / 2. Origin of Concepts / b. Empirical concepts
Concepts are abstracted from perceptions [Schopenhauer, by Lewis,PB]
All of our concepts are borrowed from perceptual knowledge [Schopenhauer]
19. Language / D. Propositions / 4. Mental Propositions
We need propositions to ascribe the same beliefs to people with different languages [Halbach]
20. Action / A. Definition of Action / 4. Action as Movement
Every true act of will is also at once and without exception a movement of the body [Schopenhauer]
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
Schopenhauer was caught in Christian ideals, because he didn't deify his 'will' [Nietzsche on Schopenhauer]
Only the will is thing-in-itself, seen both in blind nature and in human action [Schopenhauer]
As the subject of willing I am wretched, but absorption in knowledge is bliss [Schopenhauer]
20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason
If we were essentially intellect rather than will, our moral worth would depend on imagined motives [Schopenhauer]
20. Action / C. Motives for Action / 3. Acting on Reason / c. Reasons as causes
Motivation is causality seen from within [Schopenhauer]
21. Aesthetics / A. Aesthetic Experience / 1. Aesthetics
Aesthetics concerns how we can take pleasure in an object, with no reference to the will [Schopenhauer]
21. Aesthetics / A. Aesthetic Experience / 2. Aesthetic Attitude
Schopenhauer is a chief proponent of aesthetic experience as 'disinterested' [Schopenhauer, by Janaway]
21. Aesthetics / A. Aesthetic Experience / 4. Beauty
A principal pleasure of the beautiful is that it momentarily silences the will [Schopenhauer]
The beautiful is a perception of Plato's Forms, which eliminates the will [Schopenhauer]
21. Aesthetics / A. Aesthetic Experience / 6. The Sublime
The Sublime fights for will-less knowing, when faced with a beautiful threat to humanity [Schopenhauer, by Lewis,PB]
21. Aesthetics / C. Artistic Issues / 5. Objectivism in Art
Schopenhauer emphasises Ideas in art, unlike most romantics [Schopenhauer, by Lewis,PB]
21. Aesthetics / C. Artistic Issues / 6. Value of Art
The will-less contemplation of art brings a liberation from selfhood [Schopenhauer, by Gardner]
Man is more beautiful than anything else, and the loftiest purpose of art is to reveal his nature [Schopenhauer]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / c. Purpose of ethics
The only aim of our existence is to grasp that non-existence would be better [Schopenhauer]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
We should no more expect ethical theory to produce good people than aesthetics to produce artists [Schopenhauer]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / g. Moral responsibility
We clearly feel responsible for our deeds, because we are quite certain that we did them [Schopenhauer]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / b. Rational ethics
Reason can be vicious, and great crimes have to be rational [Schopenhauer]
To deduce morality from reason is blasphemy, because it is holy, and far above reason [Schopenhauer]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Man is essentially a dreadful wild animal [Schopenhauer]
Man's three basic ethical incentives are egoism, malice and compassion [Schopenhauer]
22. Metaethics / B. Value / 1. Nature of Value / d. Subjective value
Every good is essentially relative, for it has its essential nature only in its relation to a desiring will [Schopenhauer]
22. Metaethics / B. Value / 1. Nature of Value / f. Ultimate value
Will casts aside each of its temporary fulfilments, so human life has no ultimate aim [Schopenhauer, by Scruton]
22. Metaethics / B. Value / 2. Values / e. Death
Most people would probably choose non-existence at the end of their life, rather than relive the whole thing [Schopenhauer]
22. Metaethics / B. Value / 2. Values / f. Altruism
Altruistic people make less distinction than usual between themselves and others [Schopenhauer]
22. Metaethics / B. Value / 2. Values / i. Self-interest
Only self-love can motivate morality, but that also makes it worthless [Schopenhauer]
22. Metaethics / C. The Good / 2. Happiness / a. Nature of happiness
Happiness is the swift movement from desire to satisfaction, and then again on to desire [Schopenhauer]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
We can never attain happiness while our will is pursuing desires [Schopenhauer]
22. Metaethics / C. The Good / 3. Pleasure / c. Value of pleasure
Pleasure is weaker, and pain stronger, than we expect [Schopenhauer]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / a. Nature of virtue
Virtue must spring from an intuitive recognition that other people are essentially like us [Schopenhauer]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / e. Character
A man's character can be learned from a single characteristic action [Schopenhauer]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The five Chinese virtues: pity, justice, politeness, wisdom, honesty [Schopenhauer]
Buddhists wisely start with the cardinal vices [Schopenhauer]
23. Ethics / F. Existentialism / 4. Boredom
Boredom is only felt by those clever enough to need activity [Schopenhauer]
Human life is a mistake, shown by boredom, which is direct awareness of the fact [Schopenhauer]
24. Political Theory / B. Nature of a State / 1. Purpose of a State
The state only exists to defend citizens, from exterior threats, and from one another [Schopenhauer]
25. Social Practice / A. Freedoms / 1. Slavery
Poverty and slavery are virtually two words for the same thing [Schopenhauer]
25. Social Practice / A. Freedoms / 3. Free speech
The freedom of the press to sell poison outweighs its usefulness [Schopenhauer]
25. Social Practice / F. Life Issues / 4. Suicide
If suicide was quick and easy, most people would have done it by now [Schopenhauer]
25. Social Practice / F. Life Issues / 5. Sexual Morality
Would humanity still exist if sex wasn't both desired and pleasurable? [Schopenhauer]
25. Social Practice / F. Life Issues / 6. Animal Rights
Philosophy treats animals as exploitable things, ignoring the significance of their lives [Schopenhauer]
The world was made as much for animals as for man [Celsus]
26. Natural Theory / A. Speculations on Nature / 1. Nature
The essence of nature is the will to life itself [Schopenhauer]
27. Natural Reality / D. Time / 1. Nature of Time / b. Relative time
Time may be defined as the possibility of mutually exclusive conditions of the same thing [Schopenhauer]
29. Religion / B. Monotheistic Religion / 4. Christianity / a. Christianity
Christianity is a pessimistic religion, in which the world is equated with evil [Schopenhauer]
Christians presented Jesus as a new kind of logos to oppose that of the philosophers [Celsus]
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
Religion is the mythical clothing of the truth which is inaccessible to the crude human intellect [Schopenhauer]
Only religion introduces serious issues to uneducated people [Schopenhauer]
29. Religion / D. Religious Issues / 3. Problem of Evil / a. Problem of Evil
The Creator created the possibilities for worlds, so should have made a better one than this possible [Schopenhauer]