How can the existence of Paradise be inferred without recourse to the Holy Qur'an?

The existence of Paradise and its blessings are among the unseen matters that are established by the texts of revelation from the Qur’an and the Sunnah (definition), such as His Almighty saying: "The description of Paradise, which the righteous are promised, is that in it are rivers of water, the taste and smell of which are not changed..." and His saying: "Indeed, the righteous will be in Gardens and rivers." And it has been narrated from the Prophet, peace and blessings be upon him, that which indicates the greatness of its blessings. And deriving evidence from the Sunnah is deriving evidence from the Qur’an due to His Almighty saying: "And whatever the Messenger has given you—take it; and what he has forbidden you—refrain from."