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All the ideas for 'Tractatus Logico-Philosophicus', 'Law,Liberty and Morality' and 'Naming and Necessity lectures'

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200 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
What we cannot speak about we must pass over in silence [Wittgenstein]
1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
I say (contrary to Wittgenstein) that philosophy expresses what we thought we must be silent about [Ansell Pearson on Wittgenstein]
1. Philosophy / D. Nature of Philosophy / 6. Hopes for Philosophy
If a question can be framed at all, it is also possible to answer it [Wittgenstein]
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
The 'Tractatus' is a masterpiece of anti-philosophy [Badiou on Wittgenstein]
This work solves all the main problems, but that has little value [Wittgenstein]
Once you understand my book you will see that it is nonsensical [Wittgenstein]
1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
Kripke separated semantics from metaphysics, rather than linking them, making the latter independent [Kripke, by Stalnaker]
1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
Analyses of concepts using entirely different terms are very inclined to fail [Kripke]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Our language is an aspect of biology, and so its inner logic is opaque [Wittgenstein]
Most philosophical questions arise from failing to understand the logic of language [Wittgenstein]
The limits of my language means the limits of my world [Wittgenstein]
All complex statements can be resolved into constituents and descriptions [Wittgenstein]
1. Philosophy / F. Analytic Philosophy / 7. Limitations of Analysis
This book says we should either say it clearly, or shut up [Wittgenstein]
1. Philosophy / G. Scientific Philosophy / 3. Scientism
Science is all the true propositions [Wittgenstein]
2. Reason / B. Laws of Thought / 6. Ockham's Razor
If a sign is useless it is meaningless; that is the point of Ockham's maxim [Wittgenstein]
2. Reason / D. Definition / 2. Aims of Definition
Some definitions aim to fix a reference rather than give a meaning [Kripke]
3. Truth / B. Truthmakers / 2. Truthmaker Relation
The best account of truth-making is isomorphism [Wittgenstein, by Mulligan/Simons/Smith]
3. Truth / B. Truthmakers / 5. What Makes Truths / c. States of affairs make truths
He says the world is the facts because it is the facts which fix all the truths [Wittgenstein, by Morris,M]
3. Truth / B. Truthmakers / 11. Truthmaking and Correspondence
All truths have truth-makers, but only atomic truths correspond to them [Wittgenstein, by Rami]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Wittgenstein's picture theory is the best version of the correspondence theory of truth [Read on Wittgenstein]
Language is [propositions-elementary propositions-names]; reality is [facts-states of affairs-objects] [Wittgenstein, by Grayling]
The account of truth in the 'Tractatus' seems a perfect example of the correspondence theory [Wittgenstein, by O'Grady]
Pictures reach out to or feel reality, touching at the edges, correlating in its parts [Wittgenstein]
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Proposition elements correlate with objects, but the whole picture does not correspond to a fact [Wittgenstein, by Morris,M]
4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Kripke's modal semantics presupposes certain facts about possible worlds [Kripke, by Zalta]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic fills the world, to its limits [Wittgenstein]
Logic concerns everything that is subject to law; the rest is accident [Wittgenstein]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Wittgenstein is right that logic is just tautologies [Wittgenstein, by Russell]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Logic is a priori because it is impossible to think illogically [Wittgenstein]
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
If q implies p, that is justified by q and p, not by some 'laws' of inference [Wittgenstein]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
The propositions of logic are analytic tautologies [Wittgenstein]
5. Theory of Logic / C. Ontology of Logic / 2. Platonism in Logic
Wittgenstein convinced Russell that logic is tautologies, not Platonic forms [Wittgenstein, by Monk]
5. Theory of Logic / D. Assumptions for Logic / 3. Contradiction
Two colours in the same place is ruled out by the logical structure of colour [Wittgenstein]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
The sign of identity is not allowed in 'Tractatus' [Wittgenstein, by Bostock]
The identity sign is not essential in logical notation, if every sign has a different meaning [Wittgenstein, by Ramsey]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Apparent logical form may not be real logical form [Wittgenstein]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
My fundamental idea is that the 'logical constants' do not represent [Wittgenstein]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / c. not
'Not' isn't an object, because not-not-p would then differ from p [Wittgenstein]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
'Object' is a pseudo-concept, properly indicated in logic by the variable x [Wittgenstein]
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
Names are primitive, and cannot be analysed [Wittgenstein]
Names are rigid, making them unlike definite descriptions [Kripke, by Sainsbury]
Names are rigid designators, which designate the same object in all possible worlds [Kripke]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
A bundle of qualities is a collection of abstractions, so it can't be a particular [Kripke]
A name can still refer even if it satisfies none of its well-known descriptions [Kripke]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
A name is primitive, and its meaning is the object [Wittgenstein]
Some references, such as 'Neptune', have to be fixed by description rather than baptism [Kripke, by Szabó]
Proper names must have referents, because they are not descriptive [Kripke, by Sainsbury]
A name's reference is not fixed by any marks or properties of the referent [Kripke]
5. Theory of Logic / G. Quantification / 1. Quantification
Wittgenstein tried unsuccessfully to reduce quantifiers to conjunctions and disjunctions [Wittgenstein, by Jacquette]
5. Theory of Logic / H. Proof Systems / 1. Proof Systems
Logical proof just explicates complicated tautologies [Wittgenstein]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logical truths are just 'by-products' of the introduction rules for logical constants [Wittgenstein, by Hacking]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Logic doesn't split into primitive and derived propositions; they all have the same status [Wittgenstein]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / a. Defining numbers
The concept of number is just what all numbers have in common [Wittgenstein]
A number is a repeated operation [Wittgenstein]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / b. Mathematics is not set theory
The theory of classes is superfluous in mathematics [Wittgenstein]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Wittgenstein hated logicism, and described it as a cancerous growth [Wittgenstein, by Monk]
The logic of the world is shown by tautologies in logic, and by equations in mathematics [Wittgenstein]
7. Existence / A. Nature of Existence / 1. Nature of Existence
The world is facts, not things. Facts determine the world, and the world divides into facts [Wittgenstein]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
The 'Tractatus' is an extreme example of 'Logical Atomism' [Wittgenstein, by Grayling]
In atomic facts the objects hang together like chain links [Wittgenstein]
The structure of an atomic fact is how its objects combine; this possibility is its form [Wittgenstein]
If a proposition is elementary, no other elementary proposition contradicts it [Wittgenstein]
Analysis must end in elementary propositions, which are combinations of names [Wittgenstein]
Nothing can be inferred from an elementary proposition [Wittgenstein]
7. Existence / D. Theories of Reality / 2. Realism
Kripke's metaphysics (essences, kinds, rigidity) blocks the slide into sociology [Kripke, by Ladyman/Ross]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
Do his existent facts constitute the world, or determine the world? [Morris,M on Wittgenstein]
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
The world is determined by the facts, and there are no further facts [Wittgenstein]
The existence of atomic facts is a positive fact, their non-existence a negative fact [Wittgenstein]
On white paper a black spot is a positive fact and a white spot a negative fact [Wittgenstein]
8. Modes of Existence / A. Relations / 2. Internal Relations
The order of numbers is an internal relation, not an external one [Wittgenstein]
A relation is internal if it is unthinkable that its object should not possess it [Wittgenstein]
9. Objects / A. Existence of Objects / 1. Physical Objects
Objects are the substance of the world [Wittgenstein]
9. Objects / A. Existence of Objects / 5. Simples
Objects are simple [Wittgenstein]
9. Objects / A. Existence of Objects / 5. Individuation / b. Individuation by properties
Kripke individuates objects by essential modal properties (and presupposes essentialism) [Kripke, by Putnam]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Apart from the facts, there is only substance [Wittgenstein]
9. Objects / C. Structure of Objects / 6. Constitution of an Object
Given that a table is made of molecules, could it not be molecular and still be this table? [Kripke]
If we imagine this table made of ice or different wood, we are imagining a different table [Kripke]
9. Objects / D. Essence of Objects / 2. Types of Essence
For Kripke, essence is origin; for Putnam, essence is properties; for Wiggins, essence is membership of a kind [Kripke, by Mautner]
9. Objects / D. Essence of Objects / 5. Essence as Kind
Atomic number 79 is part of the nature of the gold we know [Kripke]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
An essential property is true of an object in any case where it would have existed [Kripke]
De re modality is an object having essential properties [Kripke]
9. Objects / D. Essence of Objects / 9. Essence and Properties
To know an object we must know the form and content of its internal properties [Wittgenstein, by Potter]
Important properties of an object need not be essential to it [Kripke]
9. Objects / D. Essence of Objects / 10. Essence as Species
Kripke says internal structure fixes species; I say it is genetic affinity and a common descent [Kripke, by Dummett]
Given that Nixon is indeed a human being, that he might not have been does not concern knowledge [Kripke]
9. Objects / D. Essence of Objects / 14. Knowledge of Essences
Kripke claims that some properties, only knowable posteriori, are known a priori to be essential [Kripke, by Soames]
An essence is the necessary properties, derived from an intuitive identity, in origin, type and material [Kripke, by Witt]
9. Objects / E. Objects over Time / 1. Objects over Time
No one seems to know the identity conditions for a material object (or for people) over time [Kripke]
9. Objects / E. Objects over Time / 12. Origin as Essential
If we lose track of origin, how do we show we are maintaining a reference? [Kripke, by Wiggins]
Kripke argues, of the Queen, that parents of an organism are essentially so [Kripke, by Forbes,G]
Could the actual Queen have been born of different parents? [Kripke]
Socrates can't have a necessary origin, because he might have had no 'origin' [Lowe on Kripke]
9. Objects / F. Identity among Objects / 1. Concept of Identity
Identity is not a relation between objects [Wittgenstein]
9. Objects / F. Identity among Objects / 2. Defining Identity
You can't define identity by same predicates, because two objects with same predicates is assertable [Wittgenstein]
9. Objects / F. Identity among Objects / 5. Self-Identity
Two things can't be identical, and self-identity is an empty concept [Wittgenstein]
9. Objects / F. Identity among Objects / 6. Identity between Objects
If Hesperus and Phosophorus are the same, they can't possibly be different [Kripke]
Identity statements can be contingent if they rely on descriptions [Kripke]
10. Modality / A. Necessity / 2. Nature of Necessity
Kripke says his necessary a posteriori examples are known a priori to be necessary [Kripke, by Mackie,P]
10. Modality / A. Necessity / 3. Types of Necessity
The only necessity is logical necessity [Wittgenstein]
10. Modality / A. Necessity / 7. Natural Necessity
Instead of being regularities, maybe natural laws are the weak a posteriori necessities of Kripke [Kripke, by Psillos]
Physical necessity may be necessity in the highest degree [Kripke]
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
The tautologies of logic show the logic of language and the world [Wittgenstein]
Kripke separates necessary and a priori, proposing necessary a posteriori and contingent a priori examples [Kripke, by O'Grady]
A priori = Necessary because we imagine all worlds, and we know without looking at actuality? [Kripke]
10. Modality / D. Knowledge of Modality / 2. A Priori Contingent
The meter is defined necessarily, but the stick being one meter long is contingent a priori [Kripke]
10. Modality / D. Knowledge of Modality / 3. A Posteriori Necessary
Kripke has demonstrated that some necessary truths are only knowable a posteriori [Kripke, by Chalmers]
"'Hesperus' is 'Phosphorus'" is necessarily true, if it is true, but not known a priori [Kripke]
Theoretical identities are between rigid designators, and so are necessary a posteriori [Kripke]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
What is thinkable is possible [Wittgenstein]
Kripke's essentialist necessary a posteriori opened the gap between conceivable and really possible [Soames on Kripke]
Kripke gets to the necessary a posteriori by only allowing conceivability when combined with actuality [Kripke, by Soames]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
Each thing is in a space of possible facts [Wittgenstein]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Unlike the modern view of a set of worlds, Wittgenstein thinks of a structured manifold of them [Wittgenstein, by White,RM]
An imagined world must have something in common with the real world [Wittgenstein]
Possible worlds aren't puzzling places to learn about, but places we ourselves describe [Kripke]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
To know an object you must know all its possible occurrences [Wittgenstein]
The 'form' of an object is its possible roles in facts [Wittgenstein]
If we discuss what might have happened to Nixon, we stipulate that it is about Nixon [Kripke]
Transworld identification is unproblematic, because we stipulate that we rigidly refer to something [Kripke]
A table in some possible world should not even be identified by its essential properties [Kripke]
Identification across possible worlds does not need properties, even essential ones [Kripke]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Test for rigidity by inserting into the sentence 'N might not have been N' [Kripke, by Lycan]
Kripke avoids difficulties of transworld identity by saying it is a decision, not a discovery [Kripke, by Jacquette]
Saying that natural kinds are 'rigid designators' is the same as saying they are 'indexical' [Kripke, by Putnam]
If Kripke names must still denote a thing in a non-actual situation, the statue isn't its clay [Gibbard on Kripke]
A rigid expression may refer at a world to an object not existing in that world [Kripke, by Sainsbury]
We do not begin with possible worlds and place objects in them; we begin with objects in the real world [Kripke]
It is a necessary truth that Elizabeth II was the child of two particular parents [Kripke]
10. Modality / E. Possible worlds / 3. Transworld Objects / d. Haecceitism
Two objects may only differ in being different [Wittgenstein]
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
That there might have been unicorns is false; we don't know the circumstances for unicorns [Kripke]
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
Strict solipsism is pure realism, with the self as a mere point in surrounding reality [Wittgenstein]
12. Knowledge Sources / A. A Priori Knowledge / 1. Nature of the A Priori
Kripke has breathed new life into the a priori/a posteriori distinction [Kripke, by Lowe]
Rather than 'a priori truth', it is best to stick to whether some person knows it on a priori evidence [Kripke]
A priori truths can be known independently of experience - but they don't have to be [Kripke]
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
If the truth doesn't follow from self-evidence, then self-evidence cannot justify a truth [Wittgenstein]
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
The Tractatus aims to reveal the necessities, without appealing to synthetic a priori truths [Wittgenstein, by Morris,M]
There is no a priori order of things [Wittgenstein]
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
Kripke was more successful in illuminating necessity than a priority (and their relations to analyticity) [Kripke, by Soames]
Analytic judgements are a priori, even when their content is empirical [Kripke]
Logic and maths can't say anything about the world, since, as tautologies, they are consistent with all realities [Wittgenstein, by Grayling]
12. Knowledge Sources / A. A Priori Knowledge / 10. A Priori as Subjective
Logic is a priori because we cannot think illogically [Wittgenstein]
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
No pictures are true a priori [Wittgenstein]
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Intuition is the strongest possible evidence one can have about anything [Kripke]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Doubts can't exist if they are inexpressible or unanswerable [Wittgenstein]
14. Science / B. Scientific Theories / 1. Scientific Theory
Identities like 'heat is molecule motion' are necessary (in the highest degree), not contingent [Kripke]
14. Science / B. Scientific Theories / 3. Instrumentalism
The 'Tractatus' is instrumentalist about laws of nature [Wittgenstein, by Armstrong]
14. Science / C. Induction / 2. Aims of Induction
Induction accepts the simplest law that fits our experiences [Wittgenstein]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
The modern worldview is based on the illusion that laws explain nature [Wittgenstein]
16. Persons / B. Nature of the Self / 4. Presupposition of Self
The subject stands outside our understanding of the world [Wittgenstein]
16. Persons / E. Rejecting the Self / 4. Denial of the Self
The modern idea of the subjective soul is composite, and impossible [Wittgenstein]
17. Mind and Body / A. Mind-Body Dualism / 7. Zombies
It seems logically possible to have the pain brain state without the actual pain [Kripke]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
Kripke assumes that mind-brain identity designates rigidly, which it doesn't [Armstrong on Kripke]
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / e. Modal argument
If consciousness could separate from brain, then it cannot be identical with brain [Kripke, by Papineau]
Kripke says pain is necessarily pain, but a brain state isn't necessarily painful [Kripke, by Rey]
Identity must be necessary, but pain isn't necessarily a brain state, so they aren't identical [Kripke, by Schwartz,SP]
Identity theorists seem committed to no-brain-event-no-pain, and vice versa, which seems wrong [Kripke]
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
The form of a proposition must show why nonsense is unjudgeable [Wittgenstein]
18. Thought / D. Concepts / 5. Concepts and Language / a. Concepts and language
What can be said is what can be thought, so language shows the limits of thought [Wittgenstein, by Grayling]
19. Language / A. Nature of Meaning / 2. Meaning as Mental
The 'form' of the picture is its possible combinations [Wittgenstein]
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
To understand a proposition means to know what is the case if it is true [Wittgenstein]
19. Language / A. Nature of Meaning / 5. Meaning as Verification
Good philosophy asserts science, and demonstrates the meaninglessness of metaphysics [Wittgenstein]
19. Language / B. Reference / 3. Direct Reference / a. Direct reference
Kripke derives accounts of reference and proper names from assumptions about worlds and essences [Stalnaker on Kripke]
Kripke has a definitional account of kinds, but not of naming [Almog on Kripke]
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
The important cause is not between dubbing and current use, but between the item and the speaker's information [Evans on Kripke]
We may refer through a causal chain, but still change what is referred to [Kripke]
19. Language / B. Reference / 3. Direct Reference / c. Social reference
Kripke makes reference a largely social matter, external to the mind of the speaker [Kripke, by McGinn]
Kripke's theory is important because it gives a collective account of reference [Kripke, by Putnam]
We refer through the community, going back to the original referent [Kripke]
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
Descriptive reference shows how to refer, how to identify two things, and how to challenge existence [Kripke, by PG]
It can't be necessary that Aristotle had the properties commonly attributed to him [Kripke]
19. Language / C. Assigning Meanings / 4. Compositionality
Propositions use old expressions for a new sense [Wittgenstein]
Propositions are understood via their constituents [Wittgenstein]
19. Language / C. Assigning Meanings / 10. Two-Dimensional Semantics
Rigid designation creates a puzzle - why do some necessary truths appear to be contingent? [Kripke, by Macià/Garcia-Carpentiro]
19. Language / D. Propositions / 2. Abstract Propositions / b. Propositions as possible worlds
Pictures are possible situations in logical space [Wittgenstein]
19. Language / F. Communication / 4. Private Language
Solipsism is correct, but can only be shown, not said, by the limits of my personal language [Wittgenstein]
19. Language / F. Communication / 6. Interpreting Language / a. Translation
We translate by means of proposition constituents, not by whole propositions [Wittgenstein]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / b. Defining ethics
Ethics cannot be put into words [Wittgenstein]
22. Metaethics / B. Value / 1. Nature of Value / c. Objective value
The sense of the world must lie outside the world [Wittgenstein]
22. Metaethics / C. The Good / 1. Goodness / g. Consequentialism
Conduct is not isolated from its effect on the moral code [Hart,HLA]
24. Political Theory / D. Ideologies / 5. Democracy / e. Democratic minorities
The great danger of democracy is that the oppression of the minority becomes unobjectionable [Hart,HLA]
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
In an organised society all actions have some effect on other people [Hart,HLA]
25. Social Practice / A. Freedoms / 5. Freedom of lifestyle
The value of liberty allows freedom of action, even if that distresses other people [Hart,HLA]
25. Social Practice / D. Justice / 2. The Law / a. Legal system
The principle of legality requires crimes to be precisely defined in advance of any action [Hart,HLA]
Some private moral issues are no concern of the law [Hart,HLA]
Do morals influence law? Is morality an aspect of law? Can law be morally criticised? [Hart,HLA]
Is the enforcement of morality morally justifiable? [Hart,HLA]
Modern law still suppresses practices seen as immoral, and yet harmless [Hart,HLA]
25. Social Practice / D. Justice / 3. Punishment / b. Retribution for crime
Moral wickedness of an offence is always relevant to the degree of punishment [Hart,HLA]
26. Natural Theory / B. Natural Kinds / 5. Reference to Natural Kinds
The properties that fix reference are contingent, the properties involving meaning are necessary [Kripke]
Terms for natural kinds are very close to proper names [Kripke]
26. Natural Theory / B. Natural Kinds / 6. Necessity of Kinds
Gold's atomic number might not be 79, but if it is, could non-79 stuff be gold? [Kripke]
'Cats are animals' has turned out to be a necessary truth [Kripke]
26. Natural Theory / B. Natural Kinds / 7. Critique of Kinds
Nominal essence may well be neither necessary nor sufficient for a natural kind [Kripke, by Bird]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
The scientific discovery (if correct) that gold has atomic number 79 is a necessary truth [Kripke]
Scientific discoveries about gold are necessary truths [Kripke]
Once we've found that heat is molecular motion, then that's what it is, in all possible worlds [Kripke]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / d. Knowing essences
Science searches basic structures in search of essences [Kripke]
27. Natural Reality / G. Biology / 5. Species
Tigers may lack all the properties we originally used to identify them [Kripke]
'Tiger' designates a species, and merely looking like the species is not enough [Kripke]
The original concept of 'cat' comes from paradigmatic instances [Kripke]