Combining Texts

All the ideas for 'fragments/reports', 'The Laws of Thought' and '01: Book of Genesis'

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9 ideas

4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
Boole applied normal algebra to logic, aiming at an algebra of thought [Boole, by Devlin]
     Full Idea: Boole proposed to use the entire apparatus of a school algebra class, with operations such as addition and multiplication, methods to solve equations, and the like, to produce an algebra of thought.
     From: report of George Boole (The Laws of Thought [1854]) by Keith Devlin - Goodbye Descartes Ch.3
     A reaction: The Stoics didn’t use any algebraic notation for their study of propositions, so Boole's idea launched full blown propositional logic, and the rest of modern logic followed. Nice one.
Boole's notation can represent syllogisms and propositional arguments, but not both at once [Boole, by Weiner]
     Full Idea: Boole introduced a new symbolic notation in which it was possible to represent both syllogisms and propositional arguments, ...but not both at once.
     From: report of George Boole (The Laws of Thought [1854], Ch.3) by Joan Weiner - Frege
     A reaction: How important is the development of symbolic notations for the advancement of civilisations? Is there a perfect notation, as used in logical heaven?
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Boole made logic more mathematical, with algebra, quantifiers and probability [Boole, by Friend]
     Full Idea: Boole (followed by Frege) began to turn logic from a branch of philosophy into a branch of mathematics. He brought an algebraic approach to propositions, and introduced the notion of a quantifier and a type of probabilistic reasoning.
     From: report of George Boole (The Laws of Thought [1854], 3.2) by Michèle Friend - Introducing the Philosophy of Mathematics
     A reaction: The result was that logic not only became more mathematical, but also more specialised. We now have two types of philosopher, those steeped in mathematical logic and the rest. They don't always sing from the same songsheet.
5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof
Boole's method was axiomatic, achieving economy, plus multiple interpretations [Boole, by Potter]
     Full Idea: Boole's work was an early example of the axiomatic method, whereby intellectual economy is achieved by studying a set of axioms in which the primitive terms have multiple interpretations.
     From: report of George Boole (The Laws of Thought [1854]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 02 'Boole'
     A reaction: Unclear about this. I suppose the axioms are just syntactic, and a range of semantic interpretations can be applied. Are De Morgan's Laws interpretations, or implications of the syntactic axioms? The latter, I think.
24. Political Theory / A. Basis of a State / 1. A People / a. Human distinctiveness
God made man in his own image [Anon (Tor)]
     Full Idea: And God said, let us make man in our image, after our likeness.
     From: Anon (Tor) (01: Book of Genesis [c.750 BCE], 1.26)
     A reaction: Since we are obviously not identical in every way with God, we can presumably choose in which respects we think of ourselves as being like Him. Reason, understanding, beauty, goodness, consciousness? A troublesome verse, challenged by Darwin.
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
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
26. Natural Theory / B. Natural Kinds / 5. Reference to Natural Kinds
The names of all the types of creature were given forever by Adam [Anon (Tor)]
     Full Idea: Whatsoever Adam called any living creature, the same is its name. And Adam called all the beasts by their names, and all the fowls of the air, and all the cattle of the field.
     From: Anon (Tor) (01: Book of Genesis [c.750 BCE], 02:20)
27. Natural Reality / G. Biology / 3. Evolution
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.
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
And God saw the light, that it was good [Anon (Tor)]
     Full Idea: And God saw the light, that it was good.
     From: Anon (Tor) (01: Book of Genesis [c.750 BCE], 01.04)
     A reaction: The text seems to suggest that God did not decide that it was good, but that it conformed to a standard of goodness.