# Tag Info

You should $\alpha$-rename to avoid conflict with the variable names. That is, you should prove weakening of the form: $\Gamma \vdash (\upsilon y) P$ implies $\Gamma, x : T \vdash (\upsilon y) P$. $\alpha$-equivalence and capture-avoiding substitution is an important concept to understand in type theory: I would recommend studying this concept for the ...