39 ideas
| 17749 | Post proved the consistency of propositional logic in 1921 [Walicki] |
| 17765 | Propositional language can only relate statements as the same or as different [Walicki] |
| 17764 | Boolean connectives are interpreted as functions on the set {1,0} [Walicki] |
| 17752 | The empty set is useful for defining sets by properties, when the members are not yet known [Walicki] |
| 17753 | The empty set avoids having to take special precautions in case members vanish [Walicki] |
| 17759 | Ordinals play the central role in set theory, providing the model of well-ordering [Walicki] |
| 17741 | To determine the patterns in logic, one must identify its 'building blocks' [Walicki] |
| 17747 | A 'model' of a theory specifies interpreting a language in a domain to make all theorems true [Walicki] |
| 17748 | The L-S Theorem says no theory (even of reals) says more than a natural number theory [Walicki] |
| 17761 | A compact axiomatisation makes it possible to understand a field as a whole [Walicki] |
| 17763 | Axiomatic systems are purely syntactic, and do not presuppose any interpretation [Walicki] |
| 6007 | If you know your father, but don't recognise your father veiled, you know and don't know the same person [Eubulides, by Dancy,R] |
| 6006 | If you say truly that you are lying, you are lying [Eubulides, by Dancy,R] |
| 6008 | Removing one grain doesn't destroy a heap, so a heap can't be destroyed [Eubulides, by Dancy,R] |
| 17758 | Ordinals are transitive sets of transitive sets; or transitive sets totally ordered by inclusion [Walicki] |
| 17755 | Ordinals are the empty set, union with the singleton, and any arbitrary union of ordinals [Walicki] |
| 17756 | The union of finite ordinals is the first 'limit ordinal'; 2ω is the second... [Walicki] |
| 17760 | Two infinite ordinals can represent a single infinite cardinal [Walicki] |
| 17757 | Members of ordinals are ordinals, and also subsets of ordinals [Walicki] |
| 17762 | In non-Euclidean geometry, all Euclidean theorems are valid that avoid the fifth postulate [Walicki] |
| 17754 | Inductive proof depends on the choice of the ordering [Walicki] |
| 17742 | Scotus based modality on semantic consistency, instead of on what the future could allow [Walicki] |
| 4020 | The modern self has disengaged reason, self-exploration, and personal commitment [Taylor,C] |
| 4002 | My aim is to map the connections between our sense of self and our moral understanding [Taylor,C] |
| 4006 | I can only be aware of myself as a person who changes by means of my personal history [Taylor,C] |
| 4003 | Selfhood and moral values are inextricably intertwined [Taylor,C] |
| 4021 | Willingness to risk life was the constitutive quality of the man of honour [Taylor,C] |
| 4005 | To have respect for people, you must feel their claims, or their injustices, or hold them in awe [Taylor,C] |
| 4004 | Consistency presupposes intrinsic description [Taylor,C] |
| 4010 | In later utilitarianism the modern stress on freedom leads to the rejection of paternalism [Taylor,C] |
| 22809 | The social contract sees society as constituted by and for individuals [Taylor,C] |
| 22811 | Assigning a right based on a human capacity implies that the capacity should be developed [Taylor,C] |
| 22815 | If freedom depends on society and culture, the greatest freedom is in shaping them [Taylor,C] |
| 22814 | Our reliance on other people close to us does not imply any political obligations [Taylor,C] |
| 22812 | For most people the primacy of rights mainly concerns freedom [Taylor,C] |
| 22810 | A right is not just a rule, but also asserts certain ideas of moral worth [Taylor,C] |
| 22813 | Property is not essential for life, but it may be essential for independence [Taylor,C] |
| 23417 | If the state is neutral, there won't be sufficient community to support a welfare state [Taylor,C, by Kymlicka] |
| 4009 | Nominalists defended the sovereignty of God against the idea of natural existing good and evil [Taylor,C] |