Description: Whatever follows X in the R -sequence belongs to the R -sequence beginning with X . Proposition 106 of Frege1879 p. 73. (Contributed by RP, 7-Jul-2020) (Proof modification is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypothesis | frege103.z | ||
Assertion | frege106 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | frege103.z | ||
2 | 1 | frege105 | |
3 | frege37 | ||
4 | 2 3 | ax-mp |