Step-by-step explanation:
Horatio was skeptical about the existence of the ghost and wanted proof before believing in its existence. He needed to see the ghost with his own eyes and observe its behavior to be convinced that it was not just a figment of someone's imagination or a product of their fear. Horatio was a man of reason and logic, and he believed that everything had a rational explanation. Therefore, he needed to see concrete evidence before accepting the existence of the ghost. Additionally, he may have wanted to make sure that the ghost was not a trick played by someone else, so he may have also looked for other signs or indications that could prove the ghost's authenticity.