5 ideas
13827 | Logical consequence isn't a black box (Tarski's approach); we should explain how arguments work [Prawitz] |
Full Idea: Defining logical consequence in the way Tarski does is a rather meagre result, treating an argument as a black box, observing input and output, while disregarding inner structure. We should define logical consequence on the basis of valid arguments. | |
From: Dag Prawitz (On the General Idea of Proof Theory [1974], §2) |
13826 | Model theory looks at valid sentences and consequence, but not how we know these things [Prawitz] |
Full Idea: In model theory, which has dominated the last decades, one concentrates on logically valid sentences, and what follows logically from what, but one disregards questions concerning how we know these things. | |
From: Dag Prawitz (On the General Idea of Proof Theory [1974], §1) |
5126 | A carelessly thrown brick is condemned much more if it hits someone [Smith,A, by Harman] |
Full Idea: Adam Smith wrote about the influence of fortune on moral judgements, giving nice examples. Someone carelessly throws a brick over a wall. His companion may complain even if no harm is done. But if the brick hits someone much greater condemnation ensues. | |
From: report of Adam Smith (The Theory of Moral Sentiments [1759]) by Gilbert Harman - Moral Philosophy meets social psychology 10.7.1.2 | |
A reaction: This appears to be the earliest observation of the phenomenon of moral luck, though Plato (Idea 269) endorsed the view that the luck of outcome should be taken into account in moral judgements. |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
Full Idea: Archelaus was the first person to say that the universe is boundless. | |
From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |