Combining Texts

All the ideas for 'teaching', 'Elements of Intuitionism' and 'Mathematical Truth'

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16 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Speak the truth, for this alone deifies man [Pythagoras, by Porphyry]
     Full Idea: Pythagoras advised above all things to speak the truth, for this alone deifies man.
     From: report of Pythagoras (reports [c.530 BCE]) by Porphyry - Life of Pythagoras §41
     A reaction: Idea 4421 (of Nietzsche) stands in contrast to this. I am not quite sure why speaking the truth has such a high value. I am inclined to a minimalist view, which is just that philosophy is an attempt to speak the truth, as fishermen try to catch fish.
1. Philosophy / B. History of Ideas / 2. Ancient Thought
Pythagoras discovered the numerical relation of sounds on a string [Pythagoras, by Diog. Laertius]
     Full Idea: Pythagoras discovered the numerical relation of sounds on a string.
     From: report of Pythagoras (reports [c.530 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 08.1.11
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Mathematical truth is always compromising between ordinary language and sensible epistemology [Benacerraf]
     Full Idea: Most accounts of the concept of mathematical truth can be identified with serving one or another of either semantic theory (matching it to ordinary language), or with epistemology (meshing with a reasonable view) - always at the expense of the other.
     From: Paul Benacerraf (Mathematical Truth [1973], Intro)
     A reaction: The gist is that language pulls you towards platonism, and epistemology pulls you towards empiricism. He argues that the semantics must give ground. He's right.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / m. One
For Pythagoreans 'one' is not a number, but the foundation of numbers [Pythagoras, by Watson]
     Full Idea: For Pythagoreans, one, 1, is not a true number but the 'essence' of number, out of which the number system emerges.
     From: report of Pythagoras (reports [c.530 BCE], Ch.8) by Peter Watson - Ideas Ch.8
     A reaction: I think this is right! Counting and numbers only arise once the concept of individuality and identity have arisen. Counting to one is no more than observing the law of identity. 'Two' is the big adventure.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / c. Potential infinite
Platonists ruin infinity, which is precisely a growing structure which is never completed [Dummett]
     Full Idea: The platonist destroys the whole essence of infinity, which lies in the conception of a structure which is always in growth, precisely because the process of construction is never completed.
     From: Michael Dummett (Elements of Intuitionism [1977], p.57), quoted by Thomas J. McKay - Plural Predication
     A reaction: I don't warm to intuitionism, but I warm to this conception of infinity. Completed infinities are convenient reifications for mathematicians.
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
Realists have semantics without epistemology, anti-realists epistemology but bad semantics [Benacerraf, by Colyvan]
     Full Idea: Benacerraf argues that realists about mathematical objects have a nice normal semantic but no epistemology, and anti-realists have a good epistemology but an unorthodox semantics.
     From: report of Paul Benacerraf (Mathematical Truth [1973]) by Mark Colyvan - Introduction to the Philosophy of Mathematics 1.2
The platonist view of mathematics doesn't fit our epistemology very well [Benacerraf]
     Full Idea: The principle defect of the standard (platonist) account of mathematical truth is that it appears to violate the requirement that our account be susceptible to integration into our over-all account of knowledge.
     From: Paul Benacerraf (Mathematical Truth [1973], III)
     A reaction: Unfortunately he goes on to defend a causal theory of justification (fashionable at that time, but implausible now). Nevertheless, his general point is well made. Your theory of what mathematics is had better make it knowable.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
For intuitionists it is constructed proofs (which take time) which make statements true [Dummett]
     Full Idea: For an intuitionist a mathematical statement is rendered true or false by a proof or disproof, that is, by a construction, and constructions are effected in time.
     From: Michael Dummett (Elements of Intuitionism [1977], p.336), quoted by Shaughan Lavine - Understanding the Infinite VI.2
     A reaction: Lavine is quoting this to draw attention to the difficulties of thinking of it as all taking place 'in time', especially when dealing with infinities.
22. Metaethics / B. Value / 2. Values / d. Health
Pythagoras taught that virtue is harmony, and health, and universal good, and God [Pythagoras, by Diog. Laertius]
     Full Idea: Pythagoras taught that virtue is harmony, and health, and universal good, and God.
     From: report of Pythagoras (reports [c.530 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 08.1.19
     A reaction: I like the link with health, because I consider that a bridge over the supposed fact-value gap. Very Pythagorean to think that virtue is harmony. Plato liked that thought.
23. Ethics / C. Virtue Theory / 3. Virtues / c. Justice
For Pythagoreans, justice is simply treating all people the same [Pythagoras, by Aristotle]
     Full Idea: Some even think that what is just is simple reciprocity, as the Pythagoreans maintained, because they defined justice simply as having done to one what one has done to another.
     From: report of Pythagoras (reports [c.530 BCE], 28) by Aristotle - Nicomachean Ethics 1132b22
     A reaction: One wonders what Pythagoreans made of slavery. Aristotle argues that officials, for example, have superior rights. The Pythagorean idea makes fairness the central aspect of justice, and that must at least be partly right.
26. Natural Theory / A. Speculations on Nature / 4. Mathematical Nature
When musical harmony and rhythm were discovered, similar features were seen in bodily movement [Pythagoras, by Plato]
     Full Idea: When our predecessors discovered musical scales, they also discovered similar features in bodily movement, which should also be measured numerically, and called 'tempos' and 'measures'.
     From: report of Pythagoras (reports [c.530 BCE]) by Plato - Philebus 17d
Pythagoreans define timeliness, justice and marriage in terms of numbers [Pythagoras, by Aristotle]
     Full Idea: The Pythagoreans offered definitions of a limited range of things on the basis of numbers; examples are timeliness, justice and marriage.
     From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 1078b
Pythagoreans think mathematical principles are the principles of all of nature [Pythagoras, by Aristotle]
     Full Idea: The Pythagoreans thought that the principles of mathematical entities were the principles of all entities.
     From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 985b
Pythagoreans say things imitate numbers, but Plato says things participate in numbers [Pythagoras, by Aristotle]
     Full Idea: Pythagoreans said that entities existed by imitation of the numbers, whereas Plato said that it was by participation.
     From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 987b
For Pythagoreans the entire universe is made of numbers [Pythagoras, by Aristotle]
     Full Idea: For Pythagoreans the entire universe is constructed of numbers.
     From: report of Pythagoras (reports [c.530 BCE]) by Aristotle - Metaphysics 1080b
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
The modern idea of an immortal soul was largely created by Pythagoras [Pythagoras, by Watson]
     Full Idea: The modern concept of the immortal soul is a Greek idea, which owes much to Pythagoras.
     From: report of Pythagoras (reports [c.530 BCE]) by Peter Watson - Ideas Ch.5
     A reaction: You can see why it caught on - it is a very appealing idea. Watson connects the 'modern' view with the ideas of heaven and hell. Obviously the idea of an afterlife goes a long way back (judging from the contents of ancient graves).