Combining Texts

All the ideas for 'Subjectivist's Guide to Objective Chance', 'Beginning Logic' and 'A Conversation: what is it? What is it for?'

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65 ideas

1. Philosophy / C. History of Philosophy / 1. History of Philosophy
The history of philosophy is an agent of power: how can you think if you haven't read the great names? [Deleuze]
     Full Idea: The history of philosophy has always been the agent of power in philosophy, and even in thought. It has played the oppressor's role: how can you think without having read Plato, Descartes, Kant and Heidegger.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: I find it hard to relate to this French 1960s obsession with everybody being oppressed in every conceivable way, so that 'liberation' is the only value that matters. If you ask why liberty is needed, you seem to have missed the point.
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Thought should be thrown like a stone from a war-machine [Deleuze]
     Full Idea: Thought should be thrown like a stone by a war-machine. …Isn't this what Nietzsche does with an aphorism?
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], II)
     A reaction: It sounds as if philosophy should consist of nothing but aphorisms.
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / a. Philosophy as worldly
Philosophy aims to become the official language, supporting orthodoxy and the state [Deleuze]
     Full Idea: Philosophy is shot through with the project of becoming the official language of a Pure State. The exercise of thought thus conforms to the goals of the real State, to the dominant meanings and to the requirements of the established order.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: [He cites Nietzsche's 'Schopenhauer as Educator' as the source of this] Is Karl Marx included in this generalisation, or Diogenes of Sinope? Is conservative philosophy thereby invalidated?
1. Philosophy / F. Analytic Philosophy / 7. Limitations of Analysis
When I meet objections I just move on; they never contribute anything [Deleuze]
     Full Idea: Not reflection, and objections are even worse. Every time someone puts an objection to me, I want to say: 'OK, OK, let's get on to something else'. Objections have never contributed anything.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: I know it is heresy in analytic philosophy, but I love this! In analytic seminars you can barely complete your first sentence before someone interrupts. It's like road range - the philosophical mind state is always poised to attack, attack.
1. Philosophy / H. Continental Philosophy / 1. Continental Philosophy
We must create new words, and treat them as normal, and as if designating real things. [Deleuze]
     Full Idea: Let us create extraordinary words, on condition that they be put to the most ordinary use and that the entity they designate be made to exist in the same way as the most common object.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: This sounds like the attitude of someone creating a computer game. A language game! The idea is to create concepts with which to 'palpitate' our conceptual scheme, in order to reveal it, and thus put it within our power.
2. Reason / C. Styles of Reason / 1. Dialectic
Don't assess ideas for truth or justice; look for another idea, and establish a relationship with it [Deleuze]
     Full Idea: You should not try to find whether an idea is just or correct. You should look for a completely different idea, elsewhere, in another area, so that something passes between the two which is neither in one nor the other.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: Neither relativism nor dialectic. Sounds like just having fun with ideas, but a commentator tells me it is a strategy for liberating our thought, following an agenda created by Nietzsche.
Dualisms can be undone from within, by tracing connections, and drawing them to a new path [Deleuze]
     Full Idea: It is always possible to undo dualisms from the inside, by tracing the line of flight which passes between the two terms or the two sets …and which draws both into a non-parallel evolution. At least this does not belong to the dialectic.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], II)
     A reaction: Deleuze disliked Hegel's version of the dialectic. Not clear what he means here, but he is evidently groping for an alternative account of the reasoning process, which is interesting. Deleuze hates rigid dualisms.
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
'Contradictory' propositions always differ in truth-value [Lemmon]
     Full Idea: Two propositions are 'contradictory' if they are never both true and never both false either, which means that ¬(A↔B) is a tautology.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / a. Symbols of PL
We write the 'negation' of P (not-P) as ¬ [Lemmon]
     Full Idea: We write 'not-P' as ¬P. This is called the 'negation' of P. The 'double negation' of P (not not-P) would be written as ¬¬P.
     From: E.J. Lemmon (Beginning Logic [1965], 1.2)
     A reaction: Lemmons use of -P is no longer in use for 'not'. A tilde sign (squiggle) is also used for 'not', but some interpreters give that a subtly different meaning (involving vagueness). The sign ¬ is sometimes called 'hook' or 'corner'.
The sign |- may be read as 'therefore' [Lemmon]
     Full Idea: I introduce the sign |- to mean 'we may validly conclude'. To call it the 'assertion sign' is misleading. It may conveniently be read as 'therefore'.
     From: E.J. Lemmon (Beginning Logic [1965], 1.2)
     A reaction: [Actually no gap between the vertical and horizontal strokes of the sign] As well as meaning 'assertion', it may also mean 'it is a theorem that' (with no proof shown).
That proposition that both P and Q is their 'conjunction', written P∧Q [Lemmon]
     Full Idea: If P and Q are any two propositions, the proposition that both P and Q is called the 'conjunction' of P and Q, and is written P∧Q.
     From: E.J. Lemmon (Beginning Logic [1965], 1.3)
     A reaction: [I use the more fashionable inverted-v '∧', rather than Lemmon's '&', which no longer seems to be used] P∧Q can also be defined as ¬(¬P∨¬Q)
We write the conditional 'if P (antecedent) then Q (consequent)' as P→Q [Lemmon]
     Full Idea: We write 'if P then Q' as P→Q. This is called a 'conditional', with P as its 'antecedent', and Q as its 'consequent'.
     From: E.J. Lemmon (Beginning Logic [1965], 1.2)
     A reaction: P→Q can also be written as ¬P∨Q.
That proposition that either P or Q is their 'disjunction', written P∨Q [Lemmon]
     Full Idea: If P and Q are any two propositions, the proposition that either P or Q is called the 'disjunction' of P and Q, and is written P∨Q.
     From: E.J. Lemmon (Beginning Logic [1965], 1.3)
     A reaction: This is inclusive-or (meaning 'P, or Q, or both'), and not exlusive-or (Boolean XOR), which means 'P, or Q, but not both'. The ∨ sign is sometimes called 'vel' (Latin).
If A and B are 'interderivable' from one another we may write A -||- B [Lemmon]
     Full Idea: If we say that A and B are 'interderivable' from one another (that is, A |- B and B |- A), then we may write A -||- B.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
We write 'P if and only if Q' as P↔Q; it is also P iff Q, or (P→Q)∧(Q→P) [Lemmon]
     Full Idea: We write 'P if and only if Q' as P↔Q. It is called the 'biconditional', often abbreviate in writing as 'iff'. It also says that P is both sufficient and necessary for Q, and may be written out in full as (P→Q)∧(Q→P).
     From: E.J. Lemmon (Beginning Logic [1965], 1.4)
     A reaction: If this symbol is found in a sequence, the first move in a proof is to expand it to the full version.
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
A 'well-formed formula' follows the rules for variables, ¬, →, ∧, ∨, and ↔ [Lemmon]
     Full Idea: A 'well-formed formula' of the propositional calculus is a sequence of symbols which follows the rules for variables, ¬, →, ∧, ∨, and ↔.
     From: E.J. Lemmon (Beginning Logic [1965], 2.1)
A 'theorem' is the conclusion of a provable sequent with zero assumptions [Lemmon]
     Full Idea: A 'theorem' of logic is the conclusion of a provable sequent in which the number of assumptions is zero.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
     A reaction: This is what Quine and others call a 'logical truth'.
A wff is a 'tautology' if all assignments to variables result in the value T [Lemmon]
     Full Idea: If a well-formed formula of propositional calculus takes the value T for all possible assignments of truth-values to its variables, it is said to be a 'tautology'.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
A wff is 'contingent' if produces at least one T and at least one F [Lemmon]
     Full Idea: If a well-formed formula of propositional calculus takes at least one T and at least one F for all the assignments of truth-values to its variables, it is said to be 'contingent'.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
The 'scope' of a connective is the connective, the linked formulae, and the brackets [Lemmon]
     Full Idea: The 'scope' of a connective in a certain formula is the formulae linked by the connective, together with the connective itself and the (theoretically) encircling brackets
     From: E.J. Lemmon (Beginning Logic [1965], 2.1)
A wff is 'inconsistent' if all assignments to variables result in the value F [Lemmon]
     Full Idea: If a well-formed formula of propositional calculus takes the value F for all possible assignments of truth-values to its variables, it is said to be 'inconsistent'.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
A 'substitution-instance' is a wff formed by consistent replacing variables with wffs [Lemmon]
     Full Idea: A 'substitution-instance' is a wff which results by replacing one or more variables throughout with the same wffs (the same wff replacing each variable).
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
'Contrary' propositions are never both true, so that ¬(A∧B) is a tautology [Lemmon]
     Full Idea: If A and B are expressible in propositional calculus notation, they are 'contrary' if they are never both true, which may be tested by the truth-table for ¬(A∧B), which is a tautology if they are contrary.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
Two propositions are 'equivalent' if they mirror one another's truth-value [Lemmon]
     Full Idea: Two propositions are 'equivalent' if whenever A is true B is true, and whenever B is true A is true, in which case A↔B is a tautology.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
'Subcontrary' propositions are never both false, so that A∨B is a tautology [Lemmon]
     Full Idea: If A and B are expressible in propositional calculus notation, they are 'subcontrary' if they are never both false, which may be tested by the truth-table for A∨B, which is a tautology if they are subcontrary.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
A 'implies' B if B is true whenever A is true (so that A→B is tautologous) [Lemmon]
     Full Idea: One proposition A 'implies' a proposition B if whenever A is true B is true (but not necessarily conversely), which is only the case if A→B is tautologous. Hence B 'is implied' by A.
     From: E.J. Lemmon (Beginning Logic [1965], 2.3)
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
MPP: Given A and A→B, we may derive B [Lemmon]
     Full Idea: Modus Ponendo Ponens (MPP): Given A and A→B, we may derive B as a conclusion. B will rest on any assumptions that have been made.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
CP: Given a proof of B from A as assumption, we may derive A→B [Lemmon]
     Full Idea: Conditional Proof (CP): Given a proof of B from A as assumption, we may derive A→B as conclusion, on the remaining assumptions (if any).
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
A: we may assume any proposition at any stage [Lemmon]
     Full Idea: Assumptions (A): any proposition may be introduced at any stage of a proof.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
∧E: Given A∧B, we may derive either A or B separately [Lemmon]
     Full Idea: And-Elimination (∧E): Given A∧B, we may derive either A or B separately. The conclusions will depend on the assumptions of the premiss.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
∨E: Derive C from A∨B, if C can be derived both from A and from B [Lemmon]
     Full Idea: Or-Elimination (∨E): Given A∨B, we may derive C if it is proved from A as assumption and from B as assumption. This will also depend on prior assumptions.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
∧I: Given A and B, we may derive A∧B [Lemmon]
     Full Idea: And-Introduction (&I): Given A and B, we may derive A∧B as conclusion. This depends on their previous assumptions.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
RAA: If assuming A will prove B∧¬B, then derive ¬A [Lemmon]
     Full Idea: Reduction ad Absurdum (RAA): Given a proof of B∧¬B from A as assumption, we may derive ¬A as conclusion, depending on the remaining assumptions (if any).
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
MTT: Given ¬B and A→B, we derive ¬A [Lemmon]
     Full Idea: Modus Tollendo Tollens (MTT): Given ¬B and A→B, we derive ¬A as a conclusion. ¬A depends on any assumptions that have been made
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
DN: Given A, we may derive ¬¬A [Lemmon]
     Full Idea: Double Negation (DN): Given A, we may derive ¬¬A as a conclusion, and vice versa. The conclusion depends on the assumptions of the premiss.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
∨I: Given either A or B separately, we may derive A∨B [Lemmon]
     Full Idea: Or-Introduction (∨I): Given either A or B separately, we may derive A∨B as conclusion. This depends on the assumption of the premisses.
     From: E.J. Lemmon (Beginning Logic [1965], 1.5)
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
'Modus ponendo tollens' (MPT) says P, ¬(P ∧ Q) |- ¬Q [Lemmon]
     Full Idea: 'Modus ponendo tollens' (MPT) says that if the negation of a conjunction holds and also one of its conjuncts, then the negation of the other conjunct holds. Thus P, ¬(P ∧ Q) |- ¬Q may be introduced as a theorem.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
     A reaction: Unlike Modus Ponens and Modus Tollens, this is a derived rule.
'Modus tollendo ponens' (MTP) says ¬P, P ∨ Q |- Q [Lemmon]
     Full Idea: 'Modus tollendo ponens' (MTP) says that if a disjunction holds and also the negation of one of its disjuncts, then the other disjunct holds. Thus ¬P, P ∨ Q |- Q may be introduced as a theorem.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
     A reaction: Unlike Modus Ponens and Modus Tollens, this is a derived rule.
We can change conditionals into negated conjunctions with P→Q -||- ¬(P ∧ ¬Q) [Lemmon]
     Full Idea: The proof that P→Q -||- ¬(P ∧ ¬Q) is useful for enabling us to change conditionals into negated conjunctions
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
We can change conditionals into disjunctions with P→Q -||- ¬P ∨ Q [Lemmon]
     Full Idea: The proof that P→Q -||- ¬P ∨ Q is useful for enabling us to change conditionals into disjunctions.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
De Morgan's Laws make negated conjunctions/disjunctions into non-negated disjunctions/conjunctions [Lemmon]
     Full Idea: The forms of De Morgan's Laws [P∨Q -||- ¬(¬P ∧ ¬Q); ¬(P∨Q) -||- ¬P ∧ ¬Q; ¬(P∧Q) -||- ¬P ∨ ¬Q); P∧Q -||- ¬(¬P∨¬Q)] transform negated conjunctions and disjunctions into non-negated disjunctions and conjunctions respectively.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
The Distributive Laws can rearrange a pair of conjunctions or disjunctions [Lemmon]
     Full Idea: The Distributive Laws say that P ∧ (Q∨R) -||- (P∧Q) ∨ (P∧R), and that P ∨ (Q∨R) -||- (P∨Q) ∧ (P∨R)
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
We can change conjunctions into negated conditionals with P→Q -||- ¬(P → ¬Q) [Lemmon]
     Full Idea: The proof that P∧Q -||- ¬(P → ¬Q) is useful for enabling us to change conjunctions into negated conditionals.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Truth-tables are good for showing invalidity [Lemmon]
     Full Idea: The truth-table approach enables us to show the invalidity of argument-patterns, as well as their validity.
     From: E.J. Lemmon (Beginning Logic [1965], 2.4)
A truth-table test is entirely mechanical, but this won't work for more complex logic [Lemmon]
     Full Idea: A truth-table test is entirely mechanical, ..and in propositional logic we can even generate proofs mechanically for tautological sequences, ..but this mechanical approach breaks down with predicate calculus, and proof-discovery is an imaginative process.
     From: E.J. Lemmon (Beginning Logic [1965], 2.5)
4. Formal Logic / B. Propositional Logic PL / 4. Soundness of PL
If any of the nine rules of propositional logic are applied to tautologies, the result is a tautology [Lemmon]
     Full Idea: If any application of the nine derivation rules of propositional logic is made on tautologous sequents, we have demonstrated that the result is always a tautologous sequent. Thus the system is consistent.
     From: E.J. Lemmon (Beginning Logic [1965], 2.4)
     A reaction: The term 'sound' tends to be used now, rather than 'consistent'. See Lemmon for the proofs of each of the nine rules.
4. Formal Logic / B. Propositional Logic PL / 5. Completeness of PL
Propositional logic is complete, since all of its tautologous sequents are derivable [Lemmon]
     Full Idea: A logical system is complete is all expressions of a specified kind are derivable in it. If we specify tautologous sequent-expressions, then propositional logic is complete, because we can show that all tautologous sequents are derivable.
     From: E.J. Lemmon (Beginning Logic [1965], 2.5)
     A reaction: [See Lemmon 2.5 for details of the proofs]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC
Write '(∀x)(...)' to mean 'take any x: then...', and '(∃x)(...)' to mean 'there is an x such that....' [Lemmon]
     Full Idea: Just as '(∀x)(...)' is to mean 'take any x: then....', so we write '(∃x)(...)' to mean 'there is an x such that....'
     From: E.J. Lemmon (Beginning Logic [1965], 3.1)
     A reaction: [Actually Lemmon gives the universal quantifier symbol as '(x)', but the inverted A ('∀') seems to have replaced it these days]
'Gm' says m has property G, and 'Pmn' says m has relation P to n [Lemmon]
     Full Idea: A predicate letter followed by one name expresses a property ('Gm'), and a predicate-letter followed by two names expresses a relation ('Pmn'). We could write 'Pmno' for a complex relation like betweenness.
     From: E.J. Lemmon (Beginning Logic [1965], 3.1)
The 'symbols' are bracket, connective, term, variable, predicate letter, reverse-E [Lemmon]
     Full Idea: I define a 'symbol' (of the predicate calculus) as either a bracket or a logical connective or a term or an individual variable or a predicate-letter or reverse-E (∃).
     From: E.J. Lemmon (Beginning Logic [1965], 4.1)
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / b. Terminology of PC
Our notation uses 'predicate-letters' (for 'properties'), 'variables', 'proper names', 'connectives' and 'quantifiers' [Lemmon]
     Full Idea: Quantifier-notation might be thus: first, render into sentences about 'properties', and use 'predicate-letters' for them; second, introduce 'variables'; third, introduce propositional logic 'connectives' and 'quantifiers'. Plus letters for 'proper names'.
     From: E.J. Lemmon (Beginning Logic [1965], 3.1)
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / c. Derivations rules of PC
Universal Elimination (UE) lets us infer that an object has F, from all things having F [Lemmon]
     Full Idea: Our rule of universal quantifier elimination (UE) lets us infer that any particular object has F from the premiss that all things have F. It is a natural extension of &E (and-elimination), as universal propositions generally affirm a complex conjunction.
     From: E.J. Lemmon (Beginning Logic [1965], 3.2)
Predicate logic uses propositional connectives and variables, plus new introduction and elimination rules [Lemmon]
     Full Idea: In predicate calculus we take over the propositional connectives and propositional variables - but we need additional rules for handling quantifiers: four rules, an introduction and elimination rule for the universal and existential quantifiers.
     From: E.J. Lemmon (Beginning Logic [1965])
     A reaction: This is Lemmon's natural deduction approach (invented by Gentzen), which is largely built on introduction and elimination rules.
Universal elimination if you start with the universal, introduction if you want to end with it [Lemmon]
     Full Idea: The elimination rule for the universal quantifier concerns the use of a universal proposition as a premiss to establish some conclusion, whilst the introduction rule concerns what is required by way of a premiss for a universal proposition as conclusion.
     From: E.J. Lemmon (Beginning Logic [1965], 3.2)
     A reaction: So if you start with the universal, you need to eliminate it, and if you start without it you need to introduce it.
With finite named objects, we can generalise with &-Intro, but otherwise we need ∀-Intro [Lemmon]
     Full Idea: If there are just three objects and each has F, then by an extension of &I we are sure everything has F. This is of no avail, however, if our universe is infinitely large or if not all objects have names. We need a new device, Universal Introduction, UI.
     From: E.J. Lemmon (Beginning Logic [1965], 3.2)
UE all-to-one; UI one-to-all; EI arbitrary-to-one; EE proof-to-one [Lemmon]
     Full Idea: Univ Elim UE - if everything is F, then something is F; Univ Intro UI - if an arbitrary thing is F, everything is F; Exist Intro EI - if an arbitrary thing is F, something is F; Exist Elim EE - if a proof needed an object, there is one.
     From: E.J. Lemmon (Beginning Logic [1965], 3.3)
     A reaction: [My summary of Lemmon's four main rules for predicate calculus] This is the natural deduction approach, of trying to present the logic entirely in terms of introduction and elimination rules. See Bostock on that.
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / d. Universal quantifier ∀
If there is a finite domain and all objects have names, complex conjunctions can replace universal quantifiers [Lemmon]
     Full Idea: If all objects in a given universe had names which we knew and there were only finitely many of them, then we could always replace a universal proposition about that universe by a complex conjunction.
     From: E.J. Lemmon (Beginning Logic [1965], 3.2)
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
'Some Frenchmen are generous' is rendered by (∃x)(Fx→Gx), and not with the conditional → [Lemmon]
     Full Idea: It is a common mistake to render 'some Frenchmen are generous' by (∃x)(Fx→Gx) rather than the correct (∃x)(Fx&Gx). 'All Frenchmen are generous' is properly rendered by a conditional, and true if there are no Frenchmen.
     From: E.J. Lemmon (Beginning Logic [1965], 3.1)
     A reaction: The existential quantifier implies the existence of an x, but the universal quantifier does not.
5. Theory of Logic / B. Logical Consequence / 8. Material Implication
The paradoxes of material implication are P |- Q → P, and ¬P |- P → Q [Lemmon]
     Full Idea: The paradoxes of material implication are P |- Q → P, and ¬P |- P → Q. That is, since Napoleon was French, then if the moon is blue then Napoleon was French; and since Napoleon was not Chinese, then if Napoleon was Chinese, the moon is blue.
     From: E.J. Lemmon (Beginning Logic [1965], 2.2)
     A reaction: This is why the symbol → does not really mean the 'if...then' of ordinary English. Russell named it 'material implication' to show that it was a distinctively logical operator.
5. Theory of Logic / L. Paradox / 2. Aporiai
Before we seek solutions, it is important to invent problems [Deleuze]
     Full Idea: The art of constructing a problem is very important: you invent a problem, a problem-position, before finding a solution.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: I get the impression that Deleuze prefers problems to solutions, so the activity of exploring the problem is all that really matters. Sceptics accuse philosophers of inventing pseudo-problems. We must first know why 'problematising' is good.
7. Existence / A. Nature of Existence / 3. Being / i. Deflating being
Before Being there is politics [Deleuze]
     Full Idea: Before Being there is politics.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: [He says he is quoting Felix Guattari] I can only think that this is a very Marxist view - that politics permeates and dictates everything. This seems to tell me that I am forever controlled by something so deep and vast that I can never understand it.
15. Nature of Minds / A. Nature of Mind / 1. Mind / d. Location of mind
A meeting of man and animal can be deterritorialization (like a wasp with an orchid) [Deleuze]
     Full Idea: The wasp becomes part of the orchid's reproductive apparatus at the same time as the orchid becomes the sexual organ of the wasp. …There are becomings where a man and an animal only meet on the trajectory of a common but asymmetrical deterritorialization.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: [second bit compressed] The point here is to illustrate 'deterritorialization', a term which Deleuze got from Guattari. It seems to be where the margins of your being become unclear. Recall the externalist, anti-individualist view of mind.
16. Persons / E. Rejecting the Self / 1. Self as Indeterminate
People consist of many undetermined lines, some rigid, some supple, some 'lines of flight' [Deleuze]
     Full Idea: Things, people, are made up of varied lines, and they do not necessarily know which line they are on or where they should make the line which they are tracing pass; there is a whole geography in people, with rigid lines, supple lines, lines of flight etc.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], I)
     A reaction: An example of Deleuze creating a novel concept, in order to generate a liberating way of seeing our lives. His big focus is on 'lines of flight' (which, I think, are less restrained by local culture than the others).
25. Social Practice / A. Freedoms / 2. Freedom of belief
Some lines (of flight) are becomings which escape the system [Deleuze]
     Full Idea: There are lines which do not amount to the path of a point, which break free from structure - lines of flight, becomings, without future or past, without memory, which resist the binary machine. …The rhizome is all this.
     From: Gilles Deleuze (A Conversation: what is it? What is it for? [1977], II)
     A reaction: The binary machine enforces simplistic either/or choices. I assume the 'lines' are to replace the Self, with something much more indeterminate, active and changing.
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
Lewis later proposed the axioms at the intersection of the best theories (which may be few) [Mumford on Lewis]
     Full Idea: Later Lewis said we must choose between the intersection of the axioms of the tied best systems. He chose for laws the axioms that are in all the tied systems (but then there may be few or no axioms in the intersection).
     From: comment on David Lewis (Subjectivist's Guide to Objective Chance [1980], p.124) by Stephen Mumford - Laws in Nature