Combining Philosophers

All the ideas for Archimedes, Erik J. Olsson and Christian Wolff

unexpand these ideas     |    start again     |     specify just one area for these philosophers


9 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
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.
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz]
     Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points.
     From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13
     A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Incoherence may be more important for enquiry than coherence [Olsson]
     Full Idea: While coherence may lack the positive role many have assigned to it, ...incoherence plays an important negative role in our enquiries.
     From: Erik J. Olsson (Against Coherence [2005], 10.1)
     A reaction: [He cites Peirce as the main source for this idea] We can hardly by deeply impressed by incoherence if we have no sense of coherence. Incoherence is just one of many markers for theory failure. Missing the target, bad concepts...
Coherence is the capacity to answer objections [Olsson]
     Full Idea: According to Lehrer, coherence should be understood in terms of the capacity to answer objections.
     From: Erik J. Olsson (Against Coherence [2005], 9)
     A reaction: [Keith Lehrer 1990] We can connect this with the Greek requirement of being able to give an account [logos], which is the hallmark of understanding. I take coherence to be the best method of achieving understanding. Any understanding meets Lehrer's test.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Mere agreement of testimonies is not enough to make truth very likely [Olsson]
     Full Idea: Far from guaranteeing a high likelihood of truth by itself, testimonial agreement can apparently do so only if the circumstances are favourable as regards independence, prior probability, and individual credibility.
     From: Erik J. Olsson (Against Coherence [2005], 1)
     A reaction: This is Olson's main thesis. His targets are C.I.Lewis and Bonjour, who hoped that a mere consensus of evidence would increase verisimilitude. I don't see a problem for coherence in general, since his favourable circumstances are part of it.
Coherence is only needed if the information sources are not fully reliable [Olsson]
     Full Idea: An enquirer who is fortunate enough to have at his or her disposal fully reliable information sources has no use for coherence, the need for which arises only in the context of less than fully reliable informations sources.
     From: Erik J. Olsson (Against Coherence [2005], 2.6.2)
     A reaction: I take this to be entirely false. How do you assess reliability? 'I've seen it with my own eyes'. Why trust your eyes? In what visibility conditions do you begin to doubt your eyes? Why do rational people mistrust their intuitions?
A purely coherent theory cannot be true of the world without some contact with the world [Olsson]
     Full Idea: The Input Objection says a pure coherence theory would seem to allow that a system of beliefs be justified in spite of being utterly out of contact with the world it purports to describe, so long as it is, to a sufficient extent, coherent.
     From: Erik J. Olsson (Against Coherence [2005], 4.1)
     A reaction: Olson seems impressed by this objection, but I don't see how a system could be coherently about the world if it had no known contact with the world. Olson seems to ignore meta-coherence, which evaluates the status of the system being studied.
Extending a system makes it less probable, so extending coherence can't make it more probable [Olsson]
     Full Idea: Any non-trivial extension of a belief system is less probable than the original system, but there are extensions that are more coherent than the original system. Hence more coherence does not imply a higher probability.
     From: Erik J. Olsson (Against Coherence [2005], 6.4)
     A reaction: [Olson cites Klein and Warfield 1994; compressed] The example rightly says the extension could have high internal coherence, but not whether the extension is coherent with the system being extended.
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
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.