Sometimes the conditional you are trying to prove is particularly complex, like the one in the following derivation. One special kind of complexity of conditionals we have to pay attention to is when the conditional has other conditionals "nested" inside of it$.$

But not all nested conditionals are the same! We distinguished between Type $1$ and Type $2$ conditionals, and these two types of conditionals require different strategies when we're doing a proof.

Given the aim of this derivation, how many assumptions for conditional proof will we end up making?

$1(1)(($R & T$)->$ S$)$ A Aim:$(($T $->$ R$)->($R $->$ S$))$