| 10019 | Only what is logically complex can be defined; what is simple must be pointed to [Frege] |
| 21551 | Empirical words need ostensive definition, which makes them egocentric [Russell] |
| 18889 | Ostensive definitions needn't involve pointing, but must refer to something specific [Salmon,N] |
| 11220 | Ostensive definitions look simple, but are complex and barely explicable [Gupta] |
| 9957 | Ostensive definitions point to an object which an expression denotes [Mautner] |
| 16549 | Simple things like 'red' can be given real ostensive definitions [Lowe] |