Final answer:
Formalized proofs do not guarantee the truth of a belief or the validity of a formal system. Inferences that use false premises cannot be considered true knowledge. Gilbert Harman's argument states that a person's belief cannot be based on false premises.
Step-by-step explanation:
Formalized proofs do not make formalism true because the truth of a belief is not always appropriately connected to the evidence used to deduce that belief. In cases where the reasoning leading to a belief passes through false steps or premises, the belief cannot be considered true knowledge. Philosophers like Gilbert Harman have argued that a person's belief cannot be based on an inference that uses false premises. Therefore, formalized proofs alone cannot guarantee the truth of a belief or the validity of a formal system.