In a classical natural deduction system, when introducing an implication (${\implies}\text{I}$), we may discharge an active assumption. Consider a system where a student attempts to prove $P \implies Q$ as follows:

1. Assume $P$ (Assumption 1)
2. Assume $\neg Q$ (Assumption 2)
3. From step 1, we have $P$
4. Discharge Assumption 1 to conclude $P \implies P$
5. Conclude $P \implies Q$ Which of the following is the primary logical error in this proof?