Combining Texts

All the ideas for 'teaching', 'The Nature of Truth' and 'Elements of Mathematical Logic'

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13 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
3. Truth / D. Coherence Truth / 1. Coherence Truth
Truth is conceivability, or the systematic coherence of a significant whole [Joachim]
     Full Idea: Truth is in its essence conceivability or systematic coherence. ...[p.78] It is the systematic coherence which characterises a significant whole.
     From: Harold Joachim (The Nature of Truth [1906], p.68), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 35 'coh'
     A reaction: We obviously need to know when a whole becomes 'significant'. Potter says mystical idealists liked this because it contributed to their teleological view of the whole of reality. Presumably its roots are in Hegel.
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
Lukasiewicz's L3 logic has three truth-values, T, F and I (for 'indeterminate') [Lukasiewicz, by Fisher]
     Full Idea: In response to Aristotle's sea-battle problem, Lukasiewicz proposed a three-valued logic that has come to be known as L3. In addition to the values true and false (T and F), there is a third truth-value, I, meaning 'indeterminate' or 'possible'.
     From: report of Jan Lukasiewicz (Elements of Mathematical Logic [1928], 7.I) by Jennifer Fisher - On the Philosophy of Logic
     A reaction: [He originated the idea in 1917] In what sense is the third value a 'truth' value? Is 'I don't care' a truth-value? Or 'none of the above'? His idea means that formalization doesn't collapse when things get obscure. You park a few propositions under I.
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.
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
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
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 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
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
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).