Combining Texts

All the ideas for 'On the Question of Absolute Undecidability', 'The Advancement of Learning' and 'Three Grades of Modal Involvement'

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21 ideas

1. Philosophy / E. Nature of Metaphysics / 1. Nature of Metaphysics
Metaphysics is the best knowledge, because it is the simplest [Bacon]
     Full Idea: That knowledge is worthiest which is charged with least multiplicity, which appeareth to be metaphysic
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.6)
     A reaction: A surprising view, coming from the father of modern science, but essentially correct. Obviously metaphysics aspires to avoid multiplicity, but it is riddled not only with complexity in its researches, but massive uncertainties.
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Natural history supports physical knowledge, which supports metaphysical knowledge [Bacon]
     Full Idea: Knowledges are as pyramides, whereof history is the basis. So of natural philosophy, the basis is natural history, the stage next the basis is physic; the stage next the vertical point is metaphysic.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.6)
     A reaction: The father of modern science keeps a place for metaphysics, as the most abstract level above the physical sciences. I would say he is right. It leads to my own slogan: science is the servant of philosophy.
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Physics studies transitory matter; metaphysics what is abstracted and necessary [Bacon]
     Full Idea: Physic should contemplate that which is inherent in matter, and therefore transitory; and metaphysic that which is abstracted and fixed
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.3)
     A reaction: He cites the ancients for this view, with which he agrees. One could do worse than hang onto metaphysics as the study of necessities, but must then face the attacks of the Quineans - that knowledge of necessities is beyond us.
Physics is of material and efficient causes, metaphysics of formal and final causes [Bacon]
     Full Idea: Physic inquireth and handleth the material and efficient causes; and metaphysic handleth the formal and final causes.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.3)
     A reaction: Compare Idea 12119. This divides up Aristotle's famous Four Causes (or Explanations), outlined in 'Physics' II.3. The concept of 'matter', and the nature of 'cause' seem to me to fall with the purview of metaphysics. Interesting, though.
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner]
     Full Idea: There are many coherent stopping points in the hierarchy of increasingly strong mathematical systems, starting with strict finitism, and moving up through predicativism to the higher reaches of set theory.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], Intro)
'Reflection principles' say the whole truth about sets can't be captured [Koellner]
     Full Idea: Roughly speaking, 'reflection principles' assert that anything true in V [the set hierarchy] falls short of characterising V in that it is true within some earlier level.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 2.1)
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Whether a modal claim is true depends on how the object is described [Quine, by Fine,K]
     Full Idea: Quine says if ∃x□(x>7) makes sense, then for which object x is the condition rendered true? Specify it as '9' and it is apparently rendered true, specify it as 'the number of planets' and it is apparently rendered false.
     From: report of Willard Quine (Three Grades of Modal Involvement [1953]) by Kit Fine - Quine on Quantifying In p.105
     A reaction: This is normally characterised as Quine saying that only de dicto involvement is possible, and not de re involvement. Or that that all essences are nominal, and cannot be real.
5. Theory of Logic / G. Quantification / 1. Quantification
Objects are the values of variables, so a referentially opaque context cannot be quantified into [Quine]
     Full Idea: The objects of a theory are not properly describable as the things named by the singular terms; they are the values, rather, of the variables of quantification. ..So a referentially opaque context is one that cannot properly be quantified into.
     From: Willard Quine (Three Grades of Modal Involvement [1953], p.174)
     A reaction: The point being that you cannot accurately pick out the objects in the domain
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
We have no argument to show a statement is absolutely undecidable [Koellner]
     Full Idea: There is at present no solid argument to the effect that a given statement is absolutely undecidable.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 5.3)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
There are at least eleven types of large cardinal, of increasing logical strength [Koellner]
     Full Idea: Some of the standard large cardinals (in order of increasing (logical) strength) are: inaccessible, Mahlo, weakly compact, indescribable, Erdös, measurable, strong, Wodin, supercompact, huge etc. (...and ineffable).
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4)
     A reaction: [I don't understand how cardinals can have 'logical strength', but I pass it on anyway]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
PA is consistent as far as we can accept, and we expand axioms to overcome limitations [Koellner]
     Full Idea: To the extent that we are justified in accepting Peano Arithmetic we are justified in accepting its consistency, and so we know how to expand the axiom system so as to overcome the limitation [of Gödel's Second Theorem].
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.1)
     A reaction: Each expansion brings a limitation, but then you can expand again.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Arithmetical undecidability is always settled at the next stage up [Koellner]
     Full Idea: The arithmetical instances of undecidability that arise at one stage of the hierarchy are settled at the next.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4)
9. Objects / D. Essence of Objects / 9. Essence and Properties
Aristotelian essentialism says a thing has some necessary and some non-necessary properties [Quine]
     Full Idea: What Aristotelian essentialism says is that you can have open sentences Fx and Gx, such that ∃x(nec Fx.Gx.¬nec Gx). For example, ∃x(nec(x>5). there are just x planets. ¬nec(there are just x planets)).
     From: Willard Quine (Three Grades of Modal Involvement [1953], p.176)
     A reaction: This is a denial of 'maximal essentialism', that all of a things properties might be essential. Quine is thus denying necessity, except under a description. He may be equivocating over the reference of 'there are just 9 planets'.
10. Modality / A. Necessity / 2. Nature of Necessity
Necessity can attach to statement-names, to statements, and to open sentences [Quine]
     Full Idea: Three degrees necessity in logic or semantics: first and least is attaching a semantical predicate to the names of statements (as Nec '9>5'); second and more drastic attaches to statements themselves; third and gravest attaches to open sentences.
     From: Willard Quine (Three Grades of Modal Involvement [1953], p.158)
10. Modality / A. Necessity / 11. Denial of Necessity
Necessity is in the way in which we say things, and not things themselves [Quine]
     Full Idea: Necessity resides in the way in which we say things, and not in the things we talk about.
     From: Willard Quine (Three Grades of Modal Involvement [1953], p.176)
     A reaction: This is a culminating idea of Quine's thoroughgoing empiricism, as filtered through logical positivism. I would hardly dare to accuse Quine of a use/mention confusion (his own bęte noir), but one seems to me to be lurking here.
12. Knowledge Sources / D. Empiricism / 1. Empiricism
We don't assume there is no land, because we can only see sea [Bacon]
     Full Idea: They are ill discoverers that think there is no land, when they can see nothing but sea.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.5)
     A reaction: Just the sort of pithy remark for which Bacon is famous. It is an obvious point, but a nice corrective to anyone who wants to apply empirical principles in a rather gormless way.
14. Science / A. Basis of Science / 3. Experiment
Science moves up and down between inventions of causes, and experiments [Bacon]
     Full Idea: All true and fruitful natural philosophy hath a double scale or ladder, ascendent and descendent, ascending from experiments to the invention of causes, and descending from causes to the invention of new experiments.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.1)
     A reaction: After several hundred years, I doubt whether anyone can come up with a better account of scientific method than Bacon's.
14. Science / B. Scientific Theories / 5. Commensurability
Many different theories will fit the observed facts [Bacon]
     Full Idea: The ordinary face and view of experience is many times satisfied by several theories and philosophies.
     From: Francis Bacon (The Advancement of Learning [1605], II.VIII.5)
     A reaction: He gives as his example that the Copernican system and the Ptolemaic system both seem to satisfy all the facts. He wrote in 1605, just before Galileo's telescope. His point is regularly made in modern discussions. In this case, he was wrong!
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
People love (unfortunately) extreme generality, rather than particular knowledge [Bacon]
     Full Idea: It is the nature of the mind of man (to the extreme prejudice of knowledge) to delight in the spacious liberty of generalities, as in a champaign region, and not in the inclosures of particularity.
     From: Francis Bacon (The Advancement of Learning [1605], II.VIII.1)
     A reaction: I have to plead guilty to this myself. He may have pinpointed the key motivation behind philosophy. We all want to know things, as Aristotle said, but some of us want the broad brush, and others want the fine detail.
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / c. Purpose denied
Teleological accounts are fine in metaphysics, but they stop us from searching for the causes [Bacon]
     Full Idea: To say 'leaves are for protecting of fruit', or that 'clouds are for watering the earth', is well inquired and collected in metaphysic, but in physic they are impertinent. They are hindrances, and the search of the physical causes hath been neglected.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.7)
     A reaction: This is the standard rebellion against Aristotle which gave rise to the birth of modern science. The story has been complicated by natural selection, which bestows a sort of purpose on living things. Nowadays we pursue both paths.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
Essences are part of first philosophy, but as part of nature, not part of logic [Bacon]
     Full Idea: I assign to summary philosophy the operation of essences (as quantity, similitude, diversity, possibility), with this distinction - that they be handled as they have efficacy in nature, and not logically.
     From: Francis Bacon (The Advancement of Learning [1605], II.VII.3)
     A reaction: I take this to be a splendid motto for scientific essentialism, in a climate where modal logicians appear to have taken over the driving seat in our understanding of essences.