44 ideas
| 11051 | Frege's logical approach dominates the analytical tradition [Hanna] |
| 11054 | Scientism says most knowledge comes from the exact sciences [Hanna] |
| 11070 | 'Denying the antecedent' fallacy: φ→ψ, ¬φ, so ¬ψ [Hanna] |
| 11071 | 'Affirming the consequent' fallacy: φ→ψ, ψ, so φ [Hanna] |
| 11088 | We can list at least fourteen informal fallacies [Hanna] |
| 11059 | Circular arguments are formally valid, though informally inadmissible [Hanna] |
| 11089 | Formally, composition and division fallacies occur in mereology [Hanna] |
| 22271 | Aristotle was the first to use schematic letters in logic [Aristotle, by Potter] |
| 11060 | Aristotelian syllogisms are three-part, subject-predicate, existentially committed, with laws of thought [Aristotle, by Hanna] |
| 18909 | Aristotelian sentences are made up by one of four 'formative' connectors [Aristotle, by Engelbretsen] |
| 8080 | Aristotelian identified 256 possible syllogisms, saying that 19 are valid [Aristotle, by Devlin] |
| 13912 | Aristotle replaced Plato's noun-verb form with unions of pairs of terms by one of four 'copulae' [Aristotle, by Engelbretsen/Sayward] |
| 8071 | Aristotle listed nineteen valid syllogisms (though a few of them were wrong) [Aristotle, by Devlin] |
| 13819 | Aristotle's said some Fs are G or some Fs are not G, forgetting that there might be no Fs [Bostock on Aristotle] |
| 9403 | There are three different deductions for actual terms, necessary terms and possible terms [Aristotle] |
| 11058 | Logic is explanatorily and ontologically dependent on rational animals [Hanna] |
| 11072 | Logic is personal and variable, but it has a universal core [Hanna] |
| 11061 | Intensional consequence is based on the content of the concepts [Hanna] |
| 11148 | Deduction is when we suppose one thing, and another necessarily follows [Aristotle] |
| 18896 | Aristotle places terms at opposite ends, joined by a quantified copula [Aristotle, by Sommers] |
| 3300 | Aristotle's logic is based on the subject/predicate distinction, which leads him to substances and properties [Aristotle, by Benardete,JA] |
| 11149 | Affirming/denying sentences are universal, particular, or indeterminate [Aristotle] |
| 8079 | Aristotelian logic has two quantifiers of the subject ('all' and 'some') [Aristotle, by Devlin] |
| 11063 | Logicism struggles because there is no decent theory of analyticity [Hanna] |
| 11055 | Supervenience can add covariation, upward dependence, and nomological connection [Hanna] |
| 11083 | A sentence is necessary if it is true in a set of worlds, and nonfalse in the other worlds [Hanna] |
| 14641 | A deduction is necessary if the major (but not the minor) premise is also necessary [Aristotle] |
| 11086 | Metaphysical necessity can be 'weak' (same as logical) and 'strong' (based on essences) [Hanna] |
| 11084 | Logical necessity is truth in all logically possible worlds, because of laws and concepts [Hanna] |
| 11085 | Nomological necessity is truth in all logically possible worlds with our laws [Hanna] |
| 11077 | Intuition includes apriority, clarity, modality, authority, fallibility and no inferences [Hanna] |
| 11080 | Intuition is more like memory, imagination or understanding, than like perception [Hanna] |
| 11078 | Intuition is only outside the 'space of reasons' if all reasons are inferential [Hanna] |
| 11053 | Explanatory reduction is stronger than ontological reduction [Hanna] |
| 16861 | A false theory could hardly rival the explanatory power of natural selection [Darwin] |
| 11081 | Imagination grasps abstracta, generates images, and has its own correctness conditions [Hanna] |
| 18911 | Linguistic terms form a hierarchy, with higher terms predicable of increasing numbers of things [Aristotle, by Engelbretsen] |
| 11082 | Should we take the 'depictivist' or the 'descriptivist/propositionalist' view of mental imagery? [Hanna] |
| 11067 | Rational animals have a normative concept of necessity [Hanna] |
| 11068 | One tradition says talking is the essence of rationality; the other says the essence is logic [Hanna] |
| 11047 | Hegelian holistic rationality is the capacity to seek coherence [Hanna] |
| 11048 | Humean Instrumental rationality is the capacity to seek contingent truths [Hanna] |
| 11046 | Kantian principled rationality is recognition of a priori universal truths [Hanna] |
| 11045 | Most psychologists are now cognitivists [Hanna] |