Description: The proper substitution of a class for a variable in another variable does not modify it, in inference form. (Contributed by Giovanni Mascellani, 30-May-2019)
Ref | Expression | ||
---|---|---|---|
Hypothesis | csbconstgi.1 | |
|
Assertion | csbconstgi | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | csbconstgi.1 | |
|
2 | csbconstg | |
|
3 | 1 2 | ax-mp | |