Combining Texts

All the ideas for 'fragments/reports', 'Intro to Non-Classical Logic (1st ed)' and 'Questions on Aristotle's Physics'

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33 ideas

4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
Free logic is one of the few first-order non-classical logics [Priest,G]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
X1 x X2 x X3... x Xn indicates the 'cartesian product' of those sets [Priest,G]
<a,b&62; is a set whose members occur in the order shown [Priest,G]
a ∈ X says a is an object in set X; a ∉ X says a is not in X [Priest,G]
{x; A(x)} is a set of objects satisfying the condition A(x) [Priest,G]
{a1, a2, ...an} indicates that a set comprising just those objects [Priest,G]
Φ indicates the empty set, which has no members [Priest,G]
{a} is the 'singleton' set of a (not the object a itself) [Priest,G]
X⊂Y means set X is a 'proper subset' of set Y [Priest,G]
X⊆Y means set X is a 'subset' of set Y [Priest,G]
X = Y means the set X equals the set Y [Priest,G]
X ∩ Y indicates the 'intersection' of sets X and Y, the objects which are in both sets [Priest,G]
X∪Y indicates the 'union' of all the things in sets X and Y [Priest,G]
Y - X is the 'relative complement' of X with respect to Y; the things in Y that are not in X [Priest,G]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
The 'relative complement' is things in the second set not in the first [Priest,G]
The 'intersection' of two sets is a set of the things that are in both sets [Priest,G]
The 'union' of two sets is a set containing all the things in either of the sets [Priest,G]
The 'induction clause' says complex formulas retain the properties of their basic formulas [Priest,G]
A 'singleton' is a set with only one member [Priest,G]
A 'member' of a set is one of the objects in the set [Priest,G]
An 'ordered pair' (or ordered n-tuple) is a set with its members in a particular order [Priest,G]
A 'cartesian product' of sets is the set of all the n-tuples with one member in each of the sets [Priest,G]
A 'set' is a collection of objects [Priest,G]
The 'empty set' or 'null set' has no members [Priest,G]
A set is a 'subset' of another set if all of its members are in that set [Priest,G]
A 'proper subset' is smaller than the containing set [Priest,G]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
The empty set Φ is a subset of every set (including itself) [Priest,G]
9. Objects / C. Structure of Objects / 4. Quantity of an Object
Without magnitude a thing would retain its parts, but they would have no location [Buridan]
9. Objects / E. Objects over Time / 8. Continuity of Rivers
A thing is (less properly) the same over time if each part is succeeded by another [Buridan]
14. Science / A. Basis of Science / 2. Demonstration
Induction is not demonstration, because not all of the instances can be observed [Buridan]
14. Science / C. Induction / 2. Aims of Induction
Science is based on induction, for general truths about fire, rhubarb and magnets [Buridan]
25. Social Practice / E. Policies / 5. Education / b. Education principles
Learned men gain more in one day than others do in a lifetime [Posidonius]
27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure
Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]