3 ideas
15381 | Dyamic logics model changes between classical states, in action, belief, and computing [Uckelman] |
Full Idea: Dynamic logic gives versions of propositional, modal and predicate logics, in which the states are classical, but changes of assignments between states can be expressed, by modelling action, knowledge and belief change, and compute programs. | |
From: Sara L. Uckelman (Dynamic Logics [2010]) | |
A reaction: [compressed] |
13007 | 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. |
7399 | Even without religion, there are many guides to morality [Bacon] |
Full Idea: Atheism leaves a man to sense, to philosophy, to natural piety, to laws, to reputation; all which may be guides to an outward moral virtue, though religion were not. | |
From: Francis Bacon (17: Of Superstition [1625], p.52) | |
A reaction: One might add to Bacon's list 'contracts', or 'rational consistency', or 'self-evident human excellence', or 'natural sympathy'. This is a striking idea, which clearly made churchmen uneasy when atheism began to spread. |