Description: Inaccessible levels of the cumulative hierarchy are Grothendieck universes. (Contributed by Rohan Ridenour, 13-Aug-2023)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | inagrud.1 | |- ( ph -> I e. Inacc ) |
|
| Assertion | inagrud | |- ( ph -> ( R1 ` I ) e. Univ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | inagrud.1 | |- ( ph -> I e. Inacc ) |
|
| 2 | inatsk | |- ( I e. Inacc -> ( R1 ` I ) e. Tarski ) |
|
| 3 | 1 2 | syl | |- ( ph -> ( R1 ` I ) e. Tarski ) |
| 4 | r1tr | |- Tr ( R1 ` I ) |
|
| 5 | grutsk1 | |- ( ( ( R1 ` I ) e. Tarski /\ Tr ( R1 ` I ) ) -> ( R1 ` I ) e. Univ ) |
|
| 6 | 3 4 5 | sylancl | |- ( ph -> ( R1 ` I ) e. Univ ) |