55 ideas
| 6928 | Only that which can be an object of religion is an object of philosophy [Feuerbach] |
| 6918 | Philosophy should not focus on names, but on the determined nature of things [Feuerbach] |
| 6904 | Modern philosophy begins with Descartes' abstraction from sensation and matter [Feuerbach] |
| 6931 | Empiricism is right about ideas, but forgets man himself as one of our objects [Feuerbach] |
| 6933 | The laws of reality are also the laws of thought [Feuerbach] |
| 9724 | Until the 1960s the only semantics was truth-tables [Enderton] |
| 9703 | 'dom R' indicates the 'domain' of objects having a relation [Enderton] |
| 9705 | 'fld R' indicates the 'field' of all objects in the relation [Enderton] |
| 9704 | 'ran R' indicates the 'range' of objects being related to [Enderton] |
| 9710 | We write F:A→B to indicate that A maps into B (the output of F on A is in B) [Enderton] |
| 9707 | 'F(x)' is the unique value which F assumes for a value of x [Enderton] |
| 9712 | A relation is 'symmetric' on a set if every ordered pair has the relation in both directions [Enderton] |
| 9713 | A relation is 'transitive' if it can be carried over from two ordered pairs to a third [Enderton] |
| 9699 | The 'powerset' of a set is all the subsets of a given set [Enderton] |
| 9700 | Two sets are 'disjoint' iff their intersection is empty [Enderton] |
| 9702 | A 'domain' of a relation is the set of members of ordered pairs in the relation [Enderton] |
| 9701 | A 'relation' is a set of ordered pairs [Enderton] |
| 9706 | A 'function' is a relation in which each object is related to just one other object [Enderton] |
| 9708 | A function 'maps A into B' if the relating things are set A, and the things related to are all in B [Enderton] |
| 9709 | A function 'maps A onto B' if the relating things are set A, and the things related to are set B [Enderton] |
| 9711 | A relation is 'reflexive' on a set if every member bears the relation to itself [Enderton] |
| 9714 | A relation satisfies 'trichotomy' if all pairs are either relations, or contain identical objects [Enderton] |
| 9717 | A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second [Enderton] |
| 9715 | An 'equivalence relation' is a reflexive, symmetric and transitive binary relation [Enderton] |
| 9716 | We 'partition' a set into distinct subsets, according to each relation on its objects [Enderton] |
| 9722 | Inference not from content, but from the fact that it was said, is 'conversational implicature' [Enderton] |
| 9718 | Validity is either semantic (what preserves truth), or proof-theoretic (following procedures) [Enderton] |
| 9721 | A logical truth or tautology is a logical consequence of the empty set [Enderton] |
| 9994 | A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton] |
| 9719 | A proof theory is 'sound' if its valid inferences entail semantic validity [Enderton] |
| 9720 | A proof theory is 'complete' if semantically valid inferences entail proof-theoretic validity [Enderton] |
| 9995 | Proof in finite subsets is sufficient for proof in an infinite set [Enderton] |
| 9996 | Expressions are 'decidable' if inclusion in them (or not) can be proved [Enderton] |
| 9997 | For a reasonable language, the set of valid wff's can always be enumerated [Enderton] |
| 6919 | Absolute thought remains in another world from being [Feuerbach] |
| 19457 | Being is what is undetermined, and hence indistinguishable [Feuerbach] |
| 6920 | Being posits essence, and my essence is my being [Feuerbach] |
| 6921 | Particularity belongs to being, whereas generality belongs to thought [Feuerbach] |
| 6926 | The only true being is of the senses, perception, feeling and love [Feuerbach] |
| 9723 | Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton] |
| 6908 | Consciousness is absolute reality, and everything exists through consciousness [Feuerbach] |
| 6932 | Ideas arise through communication, and reason is reached through community [Feuerbach] |
| 6935 | In man the lowest senses of smell and taste elevate themselves to intellectual acts [Feuerbach] |
| 6925 | The new philosophy thinks of the concrete in a concrete (not a abstract) manner [Feuerbach] |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
| 6924 | Plotinus was ashamed to have a body [Feuerbach] |
| 6927 | If you love nothing, it doesn't matter whether something exists or not [Feuerbach] |
| 6934 | Man is not a particular being, like animals, but a universal being [Feuerbach] |
| 6936 | The essence of man is in community, but with distinct individuals [Feuerbach] |
| 6913 | God's existence cannot be separated from essence and concept, which can only be thought as existing [Feuerbach] |
| 6903 | If God is only an object for man, then only the essence of man is revealed in God [Feuerbach] |
| 6923 | God is what man would like to be [Feuerbach] |
| 6911 | God is for us a mere empty idea, which we fill with our own ego and essence [Feuerbach] |
| 6902 | Catholicism concerns God in himself, Protestantism what God is for man [Feuerbach] |
| 6905 | Absolute idealism is the realized divine mind of Leibnizian theism [Feuerbach] |