Combining Texts

All the ideas for 'Defending the Axioms', 'Process Metaphysics' and 'Logical Investigations'

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12 ideas

1. Philosophy / H. Continental Philosophy / 2. Phenomenology
Phenomenology is the science of essences - necessary universal structures for art, representation etc. [Husserl, by Polt]
     Full Idea: For Husserl, phenomenology must seek the essential aspects of phenomena - necessary, universal structures, such as the essence of art or the essence of representation. He sought a science of these essences.
     From: report of Edmund Husserl (Logical Investigations [1900]) by Richard Polt - Heidegger: an introduction 2 'Dilthey'
Bracketing subtracts entailments about external reality from beliefs [Husserl, by Putnam]
     Full Idea: In effect, the device of bracketing subtracts entailments from the ordinary belief locution (the entailments that refer to what is external to the thinker's mind).
     From: report of Edmund Husserl (Logical Investigations [1900]) by Hilary Putnam - Reason, Truth and History Ch.2
     A reaction: This seems to leave phenomenology as pure introspection, or as a phenomenalist description of sense-data. It is also a refusal to explain anything. That sounds quite appealing, like Keats's 'negative capability'.
Phenomenology aims to describe experience directly, rather than by its origins or causes [Husserl, by Mautner]
     Full Idea: Phenomenology, in Husserl, is an attempt to describe our experience directly, as it is, separately from its origins and development, independently of the causal explanations that historians, sociologists or psychologists might give.
     From: report of Edmund Husserl (Logical Investigations [1900]) by Thomas Mautner - Penguin Dictionary of Philosophy p.421
     A reaction: In this simple definition the concept sounds very like the modern popular use of the word 'deconstruction', though that is applied more commonly to cultural artifacts than to actual sense experience.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice paradoxically allows decomposing a sphere into two identical spheres [Maddy]
     Full Idea: One feature of the Axiom of Choice that troubled many mathematicians was the so-called Banach-Tarski paradox: using the Axiom, a sphere can be decomposed into finitely many parts and those parts reassembled into two spheres the same size as the original.
     From: Penelope Maddy (Defending the Axioms [2011], 1.3)
     A reaction: (The key is that the parts are non-measurable). To an outsider it is puzzling that the Axiom has been universally accepted, even though it produces such a result. Someone can explain that, I'm sure.
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Critics of if-thenism say that not all starting points, even consistent ones, are worth studying [Maddy]
     Full Idea: If-thenism denies that mathematics is in the business of discovering truths about abstracta. ...[their opponents] obviously don't regard any starting point, even a consistent one, as equally worthy of investigation.
     From: Penelope Maddy (Defending the Axioms [2011], 3.3)
     A reaction: I have some sympathy with if-thenism, in that you can obviously study the implications of any 'if' you like, but deep down I agree with the critics.
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Hilbert's geometry and Dedekind's real numbers were role models for axiomatization [Maddy]
     Full Idea: At the end of the nineteenth century there was a renewed emphasis on rigor, the central tool of which was axiomatization, along the lines of Hilbert's axioms for geometry and Dedekind's axioms for real numbers.
     From: Penelope Maddy (Defending the Axioms [2011], 1.3)
If two mathematical themes coincide, that suggest a single deep truth [Maddy]
     Full Idea: The fact that two apparently fruitful mathematical themes turn out to coincide makes it all the more likely that they're tracking a genuine strain of mathematical depth.
     From: Penelope Maddy (Defending the Axioms [2011], 5.3ii)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
Every infinite set of reals is either countable or of the same size as the full set of reals [Maddy]
     Full Idea: One form of the Continuum Hypothesis is the claim that every infinite set of reals is either countable or of the same size as the full set of reals.
     From: Penelope Maddy (Defending the Axioms [2011], 2.4 n40)
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set-theory tracks the contours of mathematical depth and fruitfulness [Maddy]
     Full Idea: Our set-theoretic methods track the underlying contours of mathematical depth. ...What sets are, most fundamentally, is markers for these contours ...they are maximally effective trackers of certain trains of mathematical fruitfulness.
     From: Penelope Maddy (Defending the Axioms [2011], 3.4)
     A reaction: This seems to make it more like a map of mathematics than the actual essence of mathematics.
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
The connection of arithmetic to perception has been idealised away in modern infinitary mathematics [Maddy]
     Full Idea: Ordinary perceptual cognition is most likely involved in our grasp of elementary arithmetic, but ...this connection to the physical world has long since been idealized away in the infinitary structures of contemporary pure mathematics.
     From: Penelope Maddy (Defending the Axioms [2011], 2.3)
     A reaction: Despite this, Maddy's quest is for a 'naturalistic' account of mathematics. She ends up defending 'objectivity' (and invoking Tyler Burge), rather than even modest realism. You can't 'idealise away' the counting of objects. I blame Cantor.
7. Existence / B. Change in Existence / 2. Processes
Process philosophy insists that processes are not inferior in being to substances [Rescher]
     Full Idea: Process philosophy diametrically opposes the view that denies processes or downgrades them in the order of being or of understanding by subordinating them to substantial things.
     From: Nicholas Rescher (Process Metaphysics [1996]), quoted by R.D. Ingthorsson - A Powerful Particulars View of Causation 7
     A reaction: [No page cited - nr start?] Ingthorsson quotes this in order to challenge it, and says that substances are also processes, because change is essential to them.
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Husserl says we have intellectual intuitions (of categories), as well as of the senses [Husserl, by Velarde-Mayol]
     Full Idea: The novelty of Husserl is to describe that we have intellectual intuitions, intuitions of categories as we have intuitions of sense objects.
     From: report of Edmund Husserl (Logical Investigations [1900], II.VI.24) by Victor Velarde-Mayol - On Husserl 2.4.4
     A reaction: This is 'intuitions' in Kant's sense, of something like direct apprehensions. This idea is an axiom of phenomenology, because all mental life must be bracketed, and not just the sense experience part.