Combining Texts

All the ideas for 'fragments/reports', 'fragments/reports' and 'First-order Logic, 2nd-order, Completeness'

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22 ideas

1. Philosophy / B. History of Ideas / 2. Ancient Thought
Diogenes of Apollonia was the last natural scientist [Diogenes of Apollonia, by Simplicius]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg]
Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg]
There are at least seven possible systems of semantics for second-order logic [Rossberg]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
Logical consequence is intuitively semantic, and captured by model theory [Rossberg]
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
In proof-theory, logical form is shown by the logical constants [Rossberg]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg]
5. Theory of Logic / K. Features of Logics / 4. Completeness
Completeness can always be achieved by cunning model-design [Rossberg]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
A deductive system is only incomplete with respect to a formal semantics [Rossberg]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
Each thing must be in some way unique [Diogenes of Apollonia]
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Start a thesis with something undisputable [Diogenes of Apollonia]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Perception must be an internal matter, because we can fail to perceive when we are preoccupied [Diogenes of Apollonia, by Theophrastus]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
The older Diogenes said the soul is air, made of the smallest particles [Diogenes of Apollonia]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
Diogenes of Apollonia offered the first teleological account of cosmology [Diogenes of Apollonia, by Robinson,TM]
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]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / c. Ultimate substances
Everything is ultimately a variation of one underlying thing [Diogenes of Apollonia]
Air is divine, because it is in and around everything, and arranges everything [Diogenes of Apollonia]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
Plants and animals can only come into existence if something fixes their species [Diogenes of Apollonia]
Things must retain their essential nature during change, or mixing would be impossible [Diogenes of Apollonia]
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]