32 ideas
| 8755 | Maddy replaces pure sets with just objects and perceived sets of objects [Maddy, by Shapiro] |
| 10751 | Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg] |
| 10757 | Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg] |
| 10759 | There are at least seven possible systems of semantics for second-order logic [Rossberg] |
| 10753 | Logical consequence is intuitively semantic, and captured by model theory [Rossberg] |
| 10752 | Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg] |
| 10754 | In proof-theory, logical form is shown by the logical constants [Rossberg] |
| 10756 | A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg] |
| 10758 | If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg] |
| 10761 | Completeness can always be achieved by cunning model-design [Rossberg] |
| 10755 | A deductive system is only incomplete with respect to a formal semantics [Rossberg] |
| 10718 | A natural number is a property of sets [Maddy, by Oliver] |
| 8756 | Intuition doesn't support much mathematics, and we should question its reliability [Maddy, by Shapiro] |
| 17733 | We know mind-independent mathematical truths through sets, which rest on experience [Maddy, by Jenkins] |
| 23154 | We divide mankind into friend and foe, and cooperate with one and compete with the other [Russell] |
| 23153 | Gradually loyalty to a creed increased, which could even outweigh nationality [Russell] |
| 23152 | Increasingly war expands communities, and unifies them through fear [Russell] |
| 23155 | In early societies the leaders needed cohesion, but the rest just had to obey [Russell] |
| 23156 | The economic and political advantages of great size seem to have no upper limit [Russell] |
| 23157 | Government has a negative purpose, to prevent trouble, and a positive aim of realising our desires [Russell] |
| 23151 | A monarch is known to everyone in the group, and can thus unite large groups [Russell] |
| 23167 | Power should be with smaller bodies, as long as it doesn't restrict central powers [Russell] |
| 23163 | In an anarchy universities, research, books, and even seaside holidays, would be impossible [Russell] |
| 23168 | A state is essential, to control greedy or predatory impulses [Russell] |
| 23166 | In democracy we are more aware of being governed than of our tiny share in government [Russell] |
| 23162 | Managers are just as remote from workers under nationalisation as under capitalism [Russell] |
| 23165 | Socialists say economic justice needs some state control of industries, and of foreign trade [Russell] |
| 23160 | Being a slave of society is hardly better than being a slave of a despot [Russell] |
| 23158 | Slavery began the divorce between the work and the purposes of the worker [Russell] |
| 23161 | Slaves can be just as equal as free people [Russell] |
| 23159 | Scarce goods may be denied entirely, to avoid their unequal distribution [Russell] |
| 23164 | Modern justice is seen as equality, apart from modest extra rewards for exceptional desert [Russell] |