6 ideas
| 18241 | Sufficient reason is implied by contradiction, of an insufficient possible which exists [Wolff, by Korsgaard] |
| Full Idea: Wolff believed that the principle of sufficient reason could be derived from the principle of contradiction, for there would be a contradiction in the insufficiently determined existence of a merely possible thing. | |
| From: report of Christian Wolff (works [1730]) by Christine M. Korsgaard - Intro to Ethics, Politics, Religion in Kant 'A child' | |
| A reaction: Sounds as if he might be begging to question. You would only protest against the insufficient determination of something if you already believed in the principle of sufficient reason. Nice try. |
| 17744 | De Morgan started the study of relations and their properties [De Morgan, by Walicki] |
| Full Idea: De Morgan started the sustained interest in the study of relations and their properties. | |
| From: report of Augustus De Morgan (On the Syllogism IV [1859]) by Michal Walicki - Introduction to Mathematical Logic History D.1.1 |
| 13501 | De Morgan found inferences involving relations, which eluded Aristotle's syllogistic [De Morgan, by Hart,WD] |
| Full Idea: There was a prejudice against relations (in favour of properties) but De Morgan and others that impeccable inferences turn on relations and elude Aristotle's syllogistic. Thus: All horses are animals. Hence, all heads of horses are heads of animals. | |
| From: report of Augustus De Morgan (On the Syllogism IV [1859]) by William D. Hart - The Evolution of Logic 4 | |
| A reaction: This is actually an early example of modern analytic philosophy in action. You start with the inferences, and then work back to the ontology and the definition of concepts. But in pinning down such concepts, do we miss their full meaning? |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
| From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
| A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
| Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
| From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
| A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |
| 18242 | Confucius shows that ethics can rest on reason, rather than on revelation [Wolff, by Korsgaard] |
| Full Idea: Wolff claimed that the moral philosophy of Confucius shows that ethics is accessible to natural reason and independent of revelation. | |
| From: report of Christian Wolff (works [1730]) by Christine M. Korsgaard - Intro to Ethics, Politics, Religion in Kant 'A child' | |
| A reaction: Wolff was banished for proposing this idea. |