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All the ideas for 'Mahaprajnaparamitashastra', 'True in Theory, but not in Practice' and 'Logic for Philosophy'

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60 ideas

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]
     Full Idea: Formulas provable from no premises at all are often called 'theorems'.
     From: Theodore Sider (Logic for Philosophy [2010], 2.6)
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Truth tables assume truth functionality, and are just pictures of truth functions [Sider]
     Full Idea: The method of truth tables assumes truth functionality. Truth tables are just pictures of truth functions.
     From: Theodore Sider (Logic for Philosophy [2010], 6.3)
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]
     Full Idea: Deontic accessibility seems not to be reflexive (that it ought to be true doesn't make it true). One could argue that it is serial (that there is always a world where something is acceptable).
     From: Theodore Sider (Logic for Philosophy [2010], 6.3.1)
In D we add that 'what is necessary is possible'; then tautologies are possible, and contradictions not necessary [Sider]
     Full Idea: In D we add to K a new axiom saying that 'what's necessary is possible' (□φ→◊φ), ..and it can then be proved that tautologies are possible and contradictions are not necessary.
     From: Theodore Sider (Logic for Philosophy [2010], 6.4.2)
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / f. System B
System B introduces iterated modalities [Sider]
     Full Idea: With system B we begin to be able to say something about iterated modalities. ..S4 then takes a different stand on the iterated modalities, and neither is an extension of the other.
     From: Theodore Sider (Logic for Philosophy [2010], 6.4.4)
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]
     Full Idea: S5 is the strongest system, since it has the most valid formulas. That's because it has the fewest models; it's easy to be S5-valid since there are so few potentially falsifying models. K is the weakest system, for opposite reasons.
     From: Theodore Sider (Logic for Philosophy [2010], 6.3.2)
     A reaction: Interestingly, the orthodox view is that S5 is the correct logic for metaphysics, but it sounds a bit lax. Compare Idea 13707.
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]
     Full Idea: Epistemic accessibility should be required to be reflexive (allowing Kφ→φ). S4 allows the 'KK principle', or 'positive introspection' (Kφ→KKφ), and S5 allows 'negative introspection' (¬Kφ→K¬Kφ).
     From: Theodore Sider (Logic for Philosophy [2010], 7.2)
4. Formal Logic / D. Modal Logic ML / 6. Temporal Logic
We can treat modal worlds as different times [Sider]
     Full Idea: We can think of the worlds of modal logic as being times, rather than 'possible' worlds.
     From: Theodore Sider (Logic for Philosophy [2010], 7.3.3)
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
Converse Barcan Formula: □∀αφ→∀α□φ [Sider]
     Full Idea: The Converse Barcan Formula reads □∀αφ→∀α□φ (or an equivalent using ◊).
     From: Theodore Sider (Logic for Philosophy [2010], 9.5.2)
     A reaction: I would read that as 'if all the αs happen to be φ, then αs have to be φ'. Put like that, I would have thought that it was obviously false. Sider points out that some new object could turn up which isn't φ.
The Barcan Formula ∀x□Fx→□∀xFx may be a defect in modal logic [Sider]
     Full Idea: The Barcan Formula ∀x□Fx→□∀xFx is often regarded as a defect of Simple Quantified Modal Logic, though this most clearly seen in its equivalent form ◊∃xFx→∃x◊Fx.
     From: Theodore Sider (Logic for Philosophy [2010], 9.5.2)
     A reaction: [See Idea 13719 for an explanation why it might be a defect] I translate the first one as 'if xs must be F, then they are always F', and the second one as 'for x to be possibly F, there must exist an x which is possibly F'. Modality needs existence.
System B is needed to prove the Barcan Formula [Sider]
     Full Idea: The proof of the Barcan Formula require System B.
     From: Theodore Sider (Logic for Philosophy [2010], 9.7)
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
You can employ intuitionist logic without intuitionism about mathematics [Sider]
     Full Idea: Not everyone who employs intuitionistic logic is an intuitionist about mathematics.
     From: Theodore Sider (Logic for Philosophy [2010], 7.4.1)
     A reaction: This seems worthy of note, since it may be tempting to reject the logic because of the implausibility of the philosophy of mathematics. I must take intuitionist logic more seriously.
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]
     Full Idea: On the question of the nature of genuine logical consequence, ...the most popular answer is the semantic, or model-theoretic one.
     From: Theodore Sider (Logic for Philosophy [2010], 1.5)
     A reaction: Reading the literature, one might be tempted to think that this is the only account that anyone takes seriously. Substitutional semantics seems an interesting alternative.
Maybe logical consequence is more a matter of provability than of truth-preservation [Sider]
     Full Idea: Another answer to the question about the nature of logical consequence is a proof-theoretic one, according to which it is more a matter of provability than of truth-preservation.
     From: Theodore Sider (Logic for Philosophy [2010], 1.5)
     A reaction: I don't like this, and prefer the model-theoretic or substitutional accounts. Whether you can prove that something is a logical consequence seems to me entirely separate from whether you can see that it is so. Gödel seems to agree.
Maybe logical consequence is impossibility of the premises being true and the consequent false [Sider]
     Full Idea: The 'modal' account of logical consequence is that it is not possible for the premises to be true and the consequent false (under some suitable notion of possibility).
     From: Theodore Sider (Logic for Philosophy [2010], 1.5)
     A reaction: Sider gives a nice summary of five views of logical consequence, to which Shapiro adds substitutional semantics.
Maybe logical consequence is a primitive notion [Sider]
     Full Idea: There is a 'primitivist' account, according to which logical consequence is a primitive notion.
     From: Theodore Sider (Logic for Philosophy [2010], 1.5)
     A reaction: While sympathetic to substitutional views (Idea 13674), the suggestion here pushes me towards thinking that truth must be at the root of it. The trouble, though, is that a falsehood can be a good logical consequence of other falsehoods.
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
A 'theorem' is an axiom, or the last line of a legitimate proof [Sider]
     Full Idea: A 'theorem' is defined as the last line of a proof in which each line is either an axiom or follows from earlier lines by a rule.
     From: Theodore Sider (Logic for Philosophy [2010], 9.7)
     A reaction: In other words, theorems are the axioms and their implications.
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]
     Full Idea: When a variable is not combined with a quantifier (and so is 'free'), the result is, intuitively, semantically incomplete, and incapable of truth or falsity.
     From: Theodore Sider (Logic for Philosophy [2010], 4.2)
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]
     Full Idea: Calling a function a 'total' function 'over D' means that the function must have a well-defined output (which is a member of D) whenever it is given as inputs any n members of D.
     From: Theodore Sider (Logic for Philosophy [2010], 5.2)
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ can treat 'is cold and hungry' as a single predicate [Sider]
     Full Idea: We might prefer λx(Fx∧Gx)(a) as the symbolization of 'John is cold and hungry', since it treats 'is cold and hungry' as a single predicate.
     From: Theodore Sider (Logic for Philosophy [2010], 5.5)
5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof
Good axioms should be indisputable logical truths [Sider]
     Full Idea: Since they are the foundations on which a proof rests, the axioms in a good axiomatic system ought to represent indisputable logical truths.
     From: Theodore Sider (Logic for Philosophy [2010], 2.6)
No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider]
     Full Idea: Axiomatic systems do not allow reasoning with assumptions, and therefore do not allow conditional proof or reductio ad absurdum.
     From: Theodore Sider (Logic for Philosophy [2010], 2.6)
     A reaction: Since these are two of the most basic techniques of proof which I have learned (in Lemmon), I shall avoid axiomatic proof systems at all costs, despites their foundational and Ockhamist appeal.
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]
     Full Idea: The style of proof called 'induction on formula construction' (or 'on the number of connectives', or 'on the length of the formula') rest on the fact that all formulas are built up from atomic formulas according to strict rules.
     From: Theodore Sider (Logic for Philosophy [2010], 2.7)
     A reaction: Hence the proof deconstructs the formula, and takes it back to a set of atomic formulas have already been established.
Induction has a 'base case', then an 'inductive hypothesis', and then the 'inductive step' [Sider]
     Full Idea: A proof by induction starts with a 'base case', usually that an atomic formula has some property. It then assumes an 'inductive hypothesis', that the property is true up to a certain case. The 'inductive step' then says it will be true for the next case.
     From: Theodore Sider (Logic for Philosophy [2010], 2.7)
     A reaction: [compressed]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
Natural deduction helpfully allows reasoning with assumptions [Sider]
     Full Idea: The method of natural deduction is popular in introductory textbooks since it allows reasoning with assumptions.
     From: Theodore Sider (Logic for Philosophy [2010], 2.5)
     A reaction: Reasoning with assumptions is generally easier, rather than being narrowly confined to a few tricky axioms, You gradually show that an inference holds whatever the assumption was, and so end up with the same result.
5. Theory of Logic / H. Proof Systems / 6. Sequent Calculi
We can build proofs just from conclusions, rather than from plain formulae [Sider]
     Full Idea: We can construct proofs not out of well-formed formulae ('wffs'), but out of sequents, which are some premises followed by their logical consequence. We explicitly keep track of the assumptions upon which the conclusion depends.
     From: Theodore Sider (Logic for Philosophy [2010], 2.5.1)
     A reaction: He says the method of sequents was invented by Gerhard Gentzen (the great nazi logician) in 1935. The typical starting sequents are the introduction and elimination rules. E.J. Lemmon's book, used in this database, is an example.
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]
     Full Idea: A valuation function in predicate logic will assign truth values to formulas relative to variable assignments.
     From: Theodore Sider (Logic for Philosophy [2010], 4.2)
     A reaction: Sider observes that this is a 'double' relativisation (due to Tarski), since propositional logic truth was already relative to an interpretation. Now we are relative to variable assignments as well.
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]
     Full Idea: The semantical notion of a logical truth is that of a valid formula, which is true in all interpretations. In propositional logic they are 'tautologies'.
     From: Theodore Sider (Logic for Philosophy [2010], 2.3)
     A reaction: This implies that there is a proof-theoretic account of logical truth as well. Intuitively a logical truth is a sequent which holds no matter which subject matter it refers to, so the semantic view sounds OK.
It is hard to say which are the logical truths in modal logic, especially for iterated modal operators [Sider]
     Full Idea: It isn't clear which formulas of modal propositional logic are logical truths, ...especially for sentences that contain iterations of modal operators. Is □P→□□P a logical truth? It's hard to say.
     From: Theodore Sider (Logic for Philosophy [2010], 6.3)
     A reaction: The result, of course, is that there are numerous 'systems' for modal logic, so that you can choose the one that gives you the logical truths you want. His example is valid in S4 and S5, but not in the others.
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]
     Full Idea: In model theory one normally defines some notion of truth in a model, and then uses it to define validity as truth in all models, and semantic consequence as the preservation of truth in models.
     From: Theodore Sider (Logic for Philosophy [2010], 10.1)
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]
     Full Idea: You can establish facts of the form Γ|-φ while avoiding the agonies of axiomatic proofs by reasoning directly about models to conclusions about semantic consequence, and then citing completeness.
     From: Theodore Sider (Logic for Philosophy [2010], 4.5)
     A reaction: You cite completeness by saying that anything which you have shown to be a semantic consequence must therefore be provable (in some way).
5. Theory of Logic / K. Features of Logics / 6. Compactness
Compactness surprisingly says that no contradictions can emerge when the set goes infinite [Sider]
     Full Idea: Compactness is intuitively surprising, ..because one might have thought there could be some contradiction latent within some infinite set, preventing it from being satisfiable, only discovered when you consider the whole set. But this can't happen.
     From: Theodore Sider (Logic for Philosophy [2010], 4.5)
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]
     Full Idea: A single second-order sentence has second-order semantic consequences which are all and only the truths of arithmetic, but this is cold comfort because of incompleteness; no axiomatic system draws out the consequences of this axiom.
     From: Theodore Sider (Logic for Philosophy [2010], 5.4.3)
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]
     Full Idea: For a 'precisification' we take a trivalent interpretation and preserve the T and F values, and then assign all the third values in some way to either T or F.
     From: Theodore Sider (Logic for Philosophy [2010], 3.4.5)
     A reaction: [my informal summary of Sider's formal definition]
Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider]
     Full Idea: Supervaluation preserves classical logic (even though supervaluations are three-valued), except when we add the Δ operator (meaning 'definitely' or 'determinately').
     From: Theodore Sider (Logic for Philosophy [2010], 3.4.5)
A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider]
     Full Idea: In a 'supervaluation' we take a trivalent interpretation, and assign to each wff T (or F) if it is T (or F) in every precisification, leaving the third truth-value in any other cases. The wffs are then 'supertrue' or 'superfalse' in the interpretation.
     From: Theodore Sider (Logic for Philosophy [2010], 3.4.5)
     A reaction: [my non-symbolic summary] Sider says the Ts and Fs in the precisifications are assigned 'in any way you like', so supervaluation is a purely formal idea, not a technique for eliminating vagueness.
We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider]
     Full Idea: We can introduce 'sharpenings', to make vague terms precise without disturbing their semantics. Then truth (or falsity) becomes true(false)-in-all-sharpenings. You are only 'rich' if you are rich-on-all-sharpenings of the word.
     From: Theodore Sider (Logic for Philosophy [2010], 3.4.5)
     A reaction: Not very helpful. Lots of people might be considered rich in many contexts, but very few people would be considered rich in all contexts. You are still left with some vague middle ground.
8. Modes of Existence / A. Relations / 1. Nature of Relations
A relation is a feature of multiple objects taken together [Sider]
     Full Idea: A relation is just a feature of multiple objects taken together.
     From: Theodore Sider (Logic for Philosophy [2010], 1.8)
     A reaction: Appealingly simple, especially for a logician, who can then just list the relevant objects as members of a set, and the job is done. But if everyone to the left of me is also taller than me, this won't quite do.
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]
     Full Idea: The identity of indiscernibles (∀x∀y(∀X(Xx↔Xy)→x=y) is necessarily true, provided that we construe 'property' very broadly, so that 'being a member of such-and-such set' counts as a property.
     From: Theodore Sider (Logic for Philosophy [2010], 5.4.3)
     A reaction: Sider's example is that if the two objects are the same they must both have the property of being a member of the same singleton set, which they couldn't have if they were different.
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]
     Full Idea: 'Strong necessity' requires the truth of 'necessarily φ' is all possible worlds. 'Weak necessity' merely requires that 'necessarily φ' be true in all worlds in which objects referred to within φ exist.
     From: Theodore Sider (Logic for Philosophy [2010], 9.6.3)
     A reaction: This seems to be a highly desirably distinction, given the problem of Idea 13719. It is weakly necessary that humans can't fly unaided, assuming we are referring the current feeble wingless species. That hardly seems to be strongly necessary.
10. Modality / A. Necessity / 5. Metaphysical Necessity
Maybe metaphysical accessibility is intransitive, if a world in which I am a frog is impossible [Sider]
     Full Idea: Some argue that metaphysical accessibility is intransitive. The individuals involved mustn't be too different from the actual world. A world in which I am a frog isn't metaphysically possible. Perhaps the logic is modal system B or T.
     From: Theodore Sider (Logic for Philosophy [2010], 6.3.1)
     A reaction: This sounds rather plausible and attractive to me. We don't want to say that I am necessarily the way I actually am, though, so we need criteria. Essence!
10. Modality / A. Necessity / 6. Logical Necessity
Logical truths must be necessary if anything is [Sider]
     Full Idea: On any sense of necessity, surely logical truths must be necessary.
     From: Theodore Sider (Logic for Philosophy [2010], 6.4)
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]
     Full Idea: To show the semantic difference between counterfactuals and indicative conditionals, 'If Booth hadn't shot Lincoln someone else would have' is false, but 'If Booth didn't shoot Lincoln then someone else did' is true.
     From: Theodore Sider (Logic for Philosophy [2010], 8)
     A reaction: He notes that indicative conditionals also differ in semantics from material and strict conditionals. The first example allows a world where Lincoln was not shot, but the second assumes our own world, where he was. Contextual domains?
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]
     Full Idea: There is no problem of transworld identification with de dicto modal sentence, for their evaluation does not require taking an individual from one possible world and reidentifying it in another.
     From: Theodore Sider (Logic for Philosophy [2010], 9.2)
     A reaction: If 'de dicto' is about the sentence and 'de re' is about the object (Idea 5732), how do you evaluate the sentence without at least some notion of the object to which it refers. Nec the Prime Minister chairs the cabinet. Could a poached egg do the job?
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]
     Full Idea: A problem with the Barcan Formula is it might be possible for there to exist a ghost, even though there in fact exists nothing that could be a ghost. There could have existed some 'extra' thing which could be a ghost.
     From: Theodore Sider (Logic for Philosophy [2010], 9.5.2)
     A reaction: Thus when we make modal claims, do they only refer to what actually exists, or is specified in our initial domain? Can a claim enlarge the domain? Are domains 'variable'? Simple claims about what might have existed seem to be a problem.
20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason
General rules of action also need a judgement about when to apply them [Kant]
     Full Idea: A concept of the understanding, which contains the general rule, must be supplemented by an act of judgement whereby the practitioner distinguishes instances where the rule applies from those where it does not.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], Intro)
     A reaction: This is Aristotle's phronesis, and Hart's 'rules of recognition' in law courts. So is the link between theory and practice an intellectual one, or a sort of inarticulate intuition? I like 'common sense' for this ability.
22. Metaethics / C. The Good / 2. Happiness / c. Value of happiness
Duty does not aim at an end, but gives rise to universal happiness as aim of the will [Kant]
     Full Idea: My conception of duty does not need to be based on any particular end, but rather itself occasions a new end for the human will, that of striving with all one's power towards the highest good possible on earth, the universal happiness of the whole world.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 1B)
     A reaction: I see nothing in the categorical imperative that demands 'all one's power', and nothing that specifies happiness as what has to be universalised. Nietzsche, for one, thinks happiness is overrated.
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]
     Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom.
     From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88)
     A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate').
23. Ethics / D. Deontological Ethics / 2. Duty
It can't be a duty to strive after the impossible [Kant]
     Full Idea: It would not be a duty to strive after a certain effect of our will if this effect were impossible in experience.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], Intro)
     A reaction: 'Ought implies can' has become a familiar slogan. The quickest way to get shot of a tiresome duty is to persuade yourself that it is impossible. The seemingly impossible is occasionally achieved.
23. Ethics / D. Deontological Ethics / 6. Motivation for Duty
The will's motive is the absolute law itself, and moral feeling is receptivity to law [Kant]
     Full Idea: The will must have motives. But these are not objects of physical feeling as predetermined ends in themselves. They are none other than the absolute law itself, and the will's receptivity to it as an absolute compulsion is known as moral feeling.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 1Bb)
     A reaction: This sounds like our natural motivation to get the right answer when doing arithmetic, which is the innate motivation towards truth. I once heard it said that truth is the only value. So why does Donald Trump fail to value truth?
24. Political Theory / A. Basis of a State / 3. Natural Values / c. Natural rights
There can be no restraints on freedom if reason does not reveal some basic rights [Kant]
     Full Idea: If there is nothing which commands immediate respect through reason, such as the basic rights of man, no influence can prevail upon man's arbitrary will and restrain his freedom.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-Concl)
     A reaction: I think this is the nearest Kant gets to natural rights. It is hard to see how basic rights can be identified by pure reason, without some inbuilt human values. Kant's usual move is to say denial of them leads to a contradiction, but I'm going off that.
24. Political Theory / B. Nature of a State / 2. State Legitimacy / c. Social contract
Personal contracts are for some end, but a civil state contract involves a duty to share [Kant]
     Full Idea: In all social contracts, we find a union of many individuals for some common end which they all share. But a union as an end in itself which they all ought to share …is only found in a society insofar as it constitutes a civil state i.e. a commonwealth.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2 Intro)
     A reaction: This makes a nice link between the contractarian individual morality of Hobbes and his social contract view of society. Kant seems to reject the first but accept the second. Presumably because the first implies benefit and the second implies duty.
There must be a unanimous contract that citizens accept majority decisions [Kant]
     Full Idea: The actual principle of being content with majority decisions must be accepted unanimously and embodied in a contract, and this itself must be the ultimate basis on which a civil constitution is established.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-3)
     A reaction: This is the contract which combines a social contract with democracy. We unanimously agree not to be unanimous? Cf Idea 21065. What should the minority do when the majority elect criminal Nazi leaders?
A contract is theoretical, but it can guide rulers to make laws which the whole people will accept [Kant]
     Full Idea: The original contract …is merely an idea of reason, which nonetheless has undoubted practical reality; for it can oblige every legislator to frame his laws in such a way that they could have been produced by the united will of a whole nation.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-Concl)
     A reaction: The contractualist theory of morality of Thomas Scanlon approaches this. Note that Kant says it 'can' oblige the legislators. Nothing would compel them to follow such a principle.
24. Political Theory / B. Nature of a State / 2. State Legitimacy / d. General will
A law is unjust if the whole people could not possibly agree to it [Kant]
     Full Idea: If the law is such that a whole people could not possibly agree to it …it is unjust.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-Concl)
     A reaction: Kant is explicitly trying to approximate Rousseau's general will. The categorical imperative was greatly influenced by Rousseau. The key point is not whether they accept it, but that unanimous acceptance is unthinkable. Unfair laws will fail.
24. Political Theory / B. Nature of a State / 4. Citizenship
A citizen must control his own life, and possess property or an important skill [Kant]
     Full Idea: The only qualification required by a citizen (apart, of course, from being an adult male) is that he must be his own master, and must have some property (which can include any skill, trade, fine art or science) to support himself.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-3)
     A reaction: Of course! Being one's own master evidently allows for being an employee, as long as this is a free contract, and not exploitation. Invites lots of interesting test cases. We need a Marxist commentary on this idea.
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
A lawful civil state must embody freedom, equality and independence for its members [Kant]
     Full Idea: The civil state, regarded purely as a lawful state, is based on the following a priori principles. 1) the freedom of every member as a human being, 2) the equality of each as a subject, 3) the independence of each as a subject.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2 Intro)
     A reaction: Written in 1792, three years after the start of the French Revolution. He says that a state with an inbuilt hierarchy or aristocracy is unlawful. Which freedoms, equality in what respects, and independence from what?
25. Social Practice / B. Equalities / 4. Economic equality
Citizens can rise to any rank that talent, effort and luck can achieve [Kant]
     Full Idea: Every member of the commonwealth must be entitled to reach any degree of rank which a subject can earn through his talent, his industry and his good fortune.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-2)
     A reaction: This is equality of opportunity, which is a mantra for liberals, but has been subjected to good criticisms in modern times. The main question is whether there is formal and legal equality, or actual practical equality.
25. Social Practice / C. Rights / 3. Alienating rights
You can't make a contract renouncing your right to make contracts! [Kant]
     Full Idea: No one can voluntarily renounce his rights by a contract ..to the effect that he has no rights but only duties, for such a contract would deprive him of the right to make a contract, and would thus invalidate the one he had already made.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 2-2)
     A reaction: Kant tries to establish all of his principles by showing that their denial is contradictory. But this example is blatantly wrong. King Lear didn't nullify his previous legislation when he abdicated, and his two daughters legally kept their territories.
25. Social Practice / E. Policies / 1. War / a. Just wars
The people (who have to fight) and not the head of state should declare a war [Kant]
     Full Idea: Each state must be organised so that the head of state, for whom the war costs nothing (for he wages it at the expense of the people) must no longer have the deciding vote on whether war is to be declared or not, for the people who pay for it must decide.
     From: Immanuel Kant (True in Theory, but not in Practice [1792], 3)
     A reaction: I would guess that he has Louis XIV particularly in mind. Imagine if Kant's proposal had been implemented in 1914. A referendum takes ages, and the people would need the facts (from the intelligence agencies).