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All the ideas for 'Mahaprajnaparamitashastra', 'Logic for Philosophy' and 'Meditations'

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161 ideas

1. Philosophy / B. History of Ideas / 5. Later European Thought
Modern science comes from Descartes' view that knowledge doesn't need moral purity [Descartes, by Foucault]
2. Reason / A. Nature of Reason / 2. Logos
Descartes impoverished the classical idea of logos, and it no longer covered human experience [Roochnik on Descartes]
2. Reason / A. Nature of Reason / 4. Aims of Reason
Reason says don't assent to uncertain principles, just as much as totally false ones [Descartes]
2. Reason / A. Nature of Reason / 7. Status of Reason
Since Plato all philosophers have followed the herd, except Descartes, stuck in superficial reason [Nietzsche on Descartes]
2. Reason / F. Fallacies / 4. Circularity
It is circular to make truth depend on believing God's existence is true [Arnauld on Descartes]
Descartes is right that in the Christian view only God can guarantee the reliability of senses [Nietzsche on Descartes]
Once it is clear that there is a God who is no deceiver, I conclude that clear and distinct perceptions must be true [Descartes]
3. Truth / A. Truth Problems / 8. Subjective Truth
My general rule is that everything that I perceive clearly and distinctly is true [Descartes]
Someone may think a thing is 'clear and distinct', but be wrong [Leibniz on Descartes]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
'Theorems' are formulas provable from no premises at all [Sider]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Truth tables assume truth functionality, and are just pictures of truth functions [Sider]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / c. System D
Intuitively, deontic accessibility seems not to be reflexive, but to be serial [Sider]
In D we add that 'what is necessary is possible'; then tautologies are possible, and contradictions not necessary [Sider]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / f. System B
System B introduces iterated modalities [Sider]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
S5 is the strongest system, since it has the most valid formulas, because it is easy to be S5-valid [Sider]
4. Formal Logic / D. Modal Logic ML / 5. Epistemic Logic
Epistemic accessibility is reflexive, and allows positive and negative introspection (KK and K¬K) [Sider]
4. Formal Logic / D. Modal Logic ML / 6. Temporal Logic
We can treat modal worlds as different times [Sider]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
Converse Barcan Formula: □∀αφ→∀α□φ [Sider]
The Barcan Formula ∀x□Fx→□∀xFx may be a defect in modal logic [Sider]
System B is needed to prove the Barcan Formula [Sider]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
You can employ intuitionist logic without intuitionism about mathematics [Sider]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
The most popular account of logical consequence is the semantic or model-theoretic one [Sider]
Maybe logical consequence is more a matter of provability than of truth-preservation [Sider]
Maybe logical consequence is impossibility of the premises being true and the consequent false [Sider]
Maybe logical consequence is a primitive notion [Sider]
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
A 'theorem' is an axiom, or the last line of a legitimate proof [Sider]
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Arithmetic and geometry achieve some certainty without worrying about existence [Descartes]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
When a variable is 'free' of the quantifier, the result seems incapable of truth or falsity [Sider]
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
A 'total' function must always produce an output for a given domain [Sider]
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ can treat 'is cold and hungry' as a single predicate [Sider]
5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof
Good axioms should be indisputable logical truths [Sider]
No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider]
5. Theory of Logic / H. Proof Systems / 3. Proof from Assumptions
Proof by induction 'on the length of the formula' deconstructs a formula into its accepted atoms [Sider]
Induction has a 'base case', then an 'inductive hypothesis', and then the 'inductive step' [Sider]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
Natural deduction helpfully allows reasoning with assumptions [Sider]
5. Theory of Logic / H. Proof Systems / 6. Sequent Calculi
We can build proofs just from conclusions, rather than from plain formulae [Sider]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
Valuations in PC assign truth values to formulas relative to variable assignments [Sider]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
The semantical notion of a logical truth is validity, being true in all interpretations [Sider]
It is hard to say which are the logical truths in modal logic, especially for iterated modal operators [Sider]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
In model theory, first define truth, then validity as truth in all models, and consequence as truth-preservation [Sider]
5. Theory of Logic / K. Features of Logics / 4. Completeness
In a complete logic you can avoid axiomatic proofs, by using models to show consequences [Sider]
5. Theory of Logic / K. Features of Logics / 6. Compactness
Compactness surprisingly says that no contradictions can emerge when the set goes infinite [Sider]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Surely maths is true even if I am dreaming? [Descartes]
I can learn the concepts of duration and number just from observing my own thoughts [Descartes]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
A single second-order sentence validates all of arithmetic - but this can't be proved axiomatically [Sider]
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
A 'precisification' of a trivalent interpretation reduces it to a bivalent interpretation [Sider]
Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider]
A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider]
We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider]
8. Modes of Existence / A. Relations / 1. Nature of Relations
A relation is a feature of multiple objects taken together [Sider]
9. Objects / B. Unity of Objects / 1. Unifying an Object / c. Unity as conceptual
If I can separate two things in my understanding, then God can separate them in reality [Descartes]
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
Substance cannot be conceived or explained to others [Gassendi on Descartes]
9. Objects / C. Structure of Objects / 7. Substratum
If we remove surface qualities from wax, we have an extended, flexible, changeable thing [Descartes]
9. Objects / D. Essence of Objects / 4. Essence as Definition
Descartes gives an essence by an encapsulating formula [Descartes, by Almog]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The identity of indiscernibles is necessarily true, if being a member of some set counts as a property [Sider]
10. Modality / A. Necessity / 3. Types of Necessity
'Strong' necessity in all possible worlds; 'weak' necessity in the worlds where the relevant objects exist [Sider]
10. Modality / A. Necessity / 5. Metaphysical Necessity
Maybe metaphysical accessibility is intransitive, if a world in which I am a frog is impossible [Sider]
10. Modality / A. Necessity / 6. Logical Necessity
Logical truths must be necessary if anything is [Sider]
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
'If B hadn't shot L someone else would have' if false; 'If B didn't shoot L, someone else did' is true [Sider]
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
We know by thought that what is done cannot be undone [Descartes]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / b. Conceivable but impossible
Pythagoras' Theorem doesn't cease to be part of the essence of triangles just because we doubt it [Arnauld on Descartes]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Transworld identity is not a problem in de dicto sentences, which needn't identify an individual [Sider]
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
Barcan Formula problem: there might have been a ghost, despite nothing existing which could be a ghost [Sider]
11. Knowledge Aims / A. Knowledge / 4. Belief / d. Cause of beliefs
Belief is not an intellectual state or act, because propositions are affirmed or denied by the will [Descartes, by Zagzebski]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
Descartes tried to model reason on maths instead of 'logos' [Roochnik on Descartes]
Labelling slightly doubtful things as false is irrational [Roochnik on Descartes]
Maybe there is only one certain fact, which is that nothing is certain [Descartes]
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Descartes transformed 'God is thinkable, so he exists' into 'I think, so I exist' [Descartes, by Feuerbach]
In the Meditations version of the Cogito he says "I am; I exist", which avoids presenting it as an argument [Descartes, by Baggini /Fosl]
If I don't think, there is no reason to think that I exist [Descartes]
Modern philosophy set the self-conscious ego in place of God [Descartes, by Feuerbach]
"I think therefore I am" is the absolute truth of consciousness [Sartre on Descartes]
I must even exist if I am being deceived by something [Descartes]
"I am, I exist" is necessarily true every time I utter it or conceive it in my mind [Descartes]
The Cogito is a transcendental argument, not a piece of a priori knowledge [Rey on Descartes]
11. Knowledge Aims / B. Certain Knowledge / 5. Cogito Critique
The Cogito proves subjective experience is basic, but makes false claims about the Self [Russell on Descartes]
Maybe 'I' am not the thinker, but something produced by thought [Nietzsche on Descartes]
The Cogito only works if you already understand what thought and existence are [Mersenne on Descartes]
It is a precondition of the use of the word 'I' that I exist [Ayer on Descartes]
The thing which experiences may be momentary, and change with the next experience [Russell on Descartes]
'I think' assumes I exist, that thinking is known and caused, and that I am doing it [Nietzsche on Descartes]
A thought doesn't imply other thoughts, or enough thoughts to make up a self [Ayer on Descartes]
That I perform an activity (thinking) doesn't prove what type of thing I am [Hobbes on Descartes]
Autistic children seem to use the 'I' concept without seeing themselves as thinkers [Segal on Descartes]
The Cogito assumes a priori the existence of substance, when actually it is a grammatical custom [Nietzsche on Descartes]
How can we infer that all thinking involves self-consciousness, just from my own case? [Kant on Descartes]
My self is not an inference from 'I think', but a presupposition of it [Kant on Descartes]
We cannot give any information a priori about the nature of the 'thing that thinks' [Kant on Descartes]
The fact that I am a subject is not enough evidence to show that I am a substantial object [Kant on Descartes]
Descartes' claim to know his existence before his essence is misleading or absurd [Descartes, by Lowe]
Modern self-consciousness is a doubtful abstraction; only senses and feelings are certain [Feuerbach on Descartes]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
My perceiving of things may be false, but my seeming to perceive them cannot be false [Descartes]
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
I myself could be the author of all these self-delusions [Descartes]
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
A triangle has a separate non-invented nature, shown by my ability to prove facts about it [Descartes]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
For Descartes, objects have one primary quality, which is geometrical [Descartes, by Robinson,H]
12. Knowledge Sources / B. Perception / 5. Interpretation
Why does pain make us sad? [Descartes]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Dogs can make the same judgements as us about variable things [Gassendi on Descartes]
We perceive objects by intellect, not by senses or imagination [Descartes]
The wax is not perceived by the senses, but by the mind alone [Descartes]
We don't 'see' men in heavy clothes, we judge them to be men [Descartes]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
To achieve good science we must rebuild from the foundations [Descartes]
Only one certainty is needed for progress (like a lever's fulcrum) [Descartes]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Even if my body and objects are imaginary, there may be simpler things which are true [Descartes]
Descartes can't begin again, because sceptics doubt cognitive processes as well as beliefs [Pollock/Cruz on Descartes]
13. Knowledge Criteria / D. Scepticism / 3. Illusion Scepticism
If pain is felt in a lost limb, I cannot be certain that a felt pain exists in my real limbs [Descartes]
We correct sense errors with other senses, not intellect [Mersenne on Descartes]
The senses can only report, so perception errors are in the judgment [Gassendi on Descartes]
It is prudent never to trust your senses if they have deceived you even once [Descartes]
13. Knowledge Criteria / D. Scepticism / 4. Demon Scepticism
God may have created nothing, but made his creation appear to me as it does now [Descartes]
To achieve full scepticism, I imagine a devil who deceives me about the external world and my own body and senses [Descartes]
13. Knowledge Criteria / D. Scepticism / 5. Dream Scepticism
Waking actions are joined by memory to all our other actions, unlike actions of which we dream [Descartes]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
I can only sense an object if it is present, and can't fail to sense it when it is [Descartes]
15. Nature of Minds / A. Nature of Mind / 3. Mental Causation
Can the pineal gland be moved more slowly or quickly by the mind than by animal spirits? [Spinoza on Descartes]
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / c. Knowing other minds
We discovers others as well as ourselves in the Cogito [Sartre on Descartes]
15. Nature of Minds / A. Nature of Mind / 5. Unity of Mind
Faculties of the mind aren't parts, as one mind uses them [Descartes]
15. Nature of Minds / B. Features of Minds / 5. Qualia / a. Nature of qualia
Descartes put thought at the centre of the mind problem, but we put sensation [Rey on Descartes]
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
Descartes mentions many cognitive faculties, but reduces them to will and intellect [Descartes, by Schmid]
15. Nature of Minds / C. Capacities of Minds / 2. Imagination
Imagination and sensation are non-essential to mind [Descartes]
16. Persons / A. Concept of a Person / 1. Existence of Persons
Some cause must unite the separate temporal sections of a person [Descartes]
16. Persons / D. Continuity of the Self / 7. Self and Thinking
Since I only observe myself to be thinking, I conclude that that is my essence [Descartes]
I can exist without imagination and sensing, but they can't exist without me [Descartes]
For Descartes a person's essence is the mind because objects are perceived by mind, not senses [Descartes, by Feuerbach]
16. Persons / F. Free Will / 1. Nature of Free Will
Our 'will' just consists of the feeling that when we are motivated to do something, there are no external pressures [Descartes]
16. Persons / F. Free Will / 4. For Free Will
My capacity to make choices with my free will extends as far as any faculty ever could [Descartes]
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
The mind is a non-extended thing which thinks [Descartes]
Mind is not extended, unlike the body [Descartes]
Descartes is a substance AND property dualist [Descartes, by Kim]
The mind is utterly indivisible [Descartes]
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
Interaction between mental and physical seems to violate the principle of conservation of energy [Rowlands on Descartes]
17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique
The 'thinking thing' may be the physical basis of the mind [Hobbes on Descartes]
Knowing different aspects of brain/mind doesn't make them different [Rorty on Descartes]
Descartes gives no clear criterion for individuating mental substances [Cottingham on Descartes]
Does Descartes have a clear conception of how mind unites with body? [Spinoza on Descartes]
Even Descartes may concede that mental supervenes on neuroanatomical [Lycan on Descartes]
Superman's strength is indubitable, Clark Kent's is doubtful, so they are not the same? [Maslin on Descartes]
18. Thought / A. Modes of Thought / 2. Propositional Attitudes
In some thoughts I grasp a subject, but also I will or fear or affirm or deny it [Descartes]
18. Thought / A. Modes of Thought / 5. Rationality / b. Human rationality
Descartes created the modern view of rationality, as an internal feature instead of an external vision [Descartes, by Taylor,C]
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
I make errors because my will extends beyond my understanding [Descartes]
18. Thought / C. Content / 2. Ideas
True ideas are images, such as of a man, a chimera, or God [Descartes]
18. Thought / C. Content / 10. Causal Semantics
All ideas are adventitious, and come from the senses [Gassendi on Descartes]
18. Thought / D. Concepts / 2. Origin of Concepts / c. Nativist concepts
The ideas of God and of my self are innate in me [Descartes]
I can think of innumerable shapes I have never experienced [Descartes]
The idea of a supremely perfect being is within me, like the basic concepts of mathematics [Descartes]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
Many causes are quite baffling, so it is absurd to deduce causes from final purposes [Descartes]
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
There must be at least as much in the cause as there is in the effect [Descartes]
28. God / A. Divine Nature / 2. Divine Nature
Nothing apart from God could have essential existence, and such a being must be unique and eternal [Descartes]
God the creator is an intelligent, infinite, powerful substance [Descartes]
28. God / A. Divine Nature / 3. Divine Perfections
It is self-evident that deception is a natural defect, so God could not be a deceiver [Descartes]
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
Existence and God's essence are inseparable, like a valley and a mountain, or a triangle and its properties [Descartes]
One idea leads to another, but there must be an initial idea that contains the reality of all the others [Descartes]
The idea of God in my mind is like the mark a craftsman puts on his work [Descartes]
I cannot think of a supremely perfect being without the supreme perfection of existence [Descartes]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
We mustn't worship God as an image because we have no idea of him [Hobbes on Descartes]
We can never conceive of an infinite being [Gassendi on Descartes]
Descartes cannot assume that a most perfect being exists without contradictions [Leibniz on Descartes]
Existence is not a perfection; it is what makes perfection possible [Gassendi on Descartes]
29. Religion / D. Religious Issues / 3. Problem of Evil / c. Human Error
Error arises because my faculty for judging truth is not infinite [Descartes]
Since God does not wish to deceive me, my judgement won't make errors if I use it properly [Descartes]
God didn't give us good judgement even about our own lives [Gassendi on Descartes]
29. Religion / D. Religious Issues / 3. Problem of Evil / d. Natural Evil
If we ask whether God's works are perfect, we must not take a narrow viewpoint, but look at the universe as a whole [Descartes]