- Abstract propositions(in metaphysics and logic)
- Statements or claims about ideas, concepts, or numbers—things that don't have a physical form. For example, 'two plus two equals four' is abstract because the numbers themselves don't exist as physical objects you can touch.
- Attitude ascriptions(as used in philosophy of mind and language)
- The act of saying someone has a mental state or belief, like saying 'she believes it will rain' or 'he wants coffee.'
- Functional-state analyses(as used in philosophy of mind)
- Explaining something by describing what it *does* rather than what it *is*—like explaining a belief by describing how it makes you behave.
- Multiplies entities beyond necessity(as used in philosophy of logic)
- A way of saying someone is suggesting too many things exist when simpler explanations would work just as well; it's wasteful philosophically.
- Occam's Razor (implied by 'beyond necessity')(as a methodological principle in philosophy)
- A principle saying that the simplest explanation that works is usually the best one—don't assume extra things exist if you don't have to.
- Ontology(Carnap argues this enterprise is based on a mistake)
- The philosophical discipline that tries to answer hard questions about what there really is.
- abstract objects(The target of Platonist ontological claims)
- Objects referred to by singular terms in literally true sentences that cannot be paraphrased away; includes mathematical objects (e.g., numbers), propositions, properties, relations, sentence types, possible worlds, logical objects, and fictional objects.