Combining Texts

All the ideas for 'Abortion and the Doctrine of Double Effect', 'Introduction to Mathematical Logic' and 'Non-foundationalist epistemology'

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28 ideas

2. Reason / A. Nature of Reason / 6. Coherence
How can multiple statements, none of which is tenable, conjoin to yield a tenable conclusion? [Elgin]
Statements that are consistent, cotenable and supportive are roughly true [Elgin]
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
Post proved the consistency of propositional logic in 1921 [Walicki]
Propositional language can only relate statements as the same or as different [Walicki]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Boolean connectives are interpreted as functions on the set {1,0} [Walicki]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The empty set is useful for defining sets by properties, when the members are not yet known [Walicki]
The empty set avoids having to take special precautions in case members vanish [Walicki]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
Ordinals play the central role in set theory, providing the model of well-ordering [Walicki]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
To determine the patterns in logic, one must identify its 'building blocks' [Walicki]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A 'model' of a theory specifies interpreting a language in a domain to make all theorems true [Walicki]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
The L-S Theorem says no theory (even of reals) says more than a natural number theory [Walicki]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
A compact axiomatisation makes it possible to understand a field as a whole [Walicki]
Axiomatic systems are purely syntactic, and do not presuppose any interpretation [Walicki]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Ordinals are transitive sets of transitive sets; or transitive sets totally ordered by inclusion [Walicki]
Ordinals are the empty set, union with the singleton, and any arbitrary union of ordinals [Walicki]
The union of finite ordinals is the first 'limit ordinal'; 2ω is the second... [Walicki]
Two infinite ordinals can represent a single infinite cardinal [Walicki]
Members of ordinals are ordinals, and also subsets of ordinals [Walicki]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
In non-Euclidean geometry, all Euclidean theorems are valid that avoid the fifth postulate [Walicki]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Inductive proof depends on the choice of the ordering [Walicki]
10. Modality / A. Necessity / 2. Nature of Necessity
Scotus based modality on semantic consistency, instead of on what the future could allow [Walicki]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Coherence is a justification if truth is its best explanation (not skill in creating fiction) [Elgin]
20. Action / C. Motives for Action / 5. Action Dilemmas / b. Double Effect
A 'double effect' is a foreseen but not desired side-effect, which may be forgivable [Foot]
The doctrine of double effect can excuse an outcome because it wasn't directly intended [Foot]
Double effect says foreseeing you will kill someone is not the same as intending it [Foot]
Without double effect, bad men can make us do evil by threatening something worse [Foot]
Double effect seems to rely on a distinction between what we do and what we allow [Foot]
25. Social Practice / F. Life Issues / 3. Abortion
Abortion is puzzling because we do and don't want the unborn child to have rights [Foot]