Final answer:
The Upanishads are a true departure from the earlier Vedic religion, introducing new philosophical ideas and focusing on internal spirituality rather than external rituals.
Step-by-step explanation:
According to Prothero, the Upanishads do indeed represent a new religious creation that is different from the Vedic religion. This is true. The Upanishads evolved from the earlier Vedic texts, providing new expressions of religious thought including concepts such as samsara (the cycle of rebirth) and karma (action and its consequences). These texts primarily include philosophical reflections and dialogues concerning the nature of reality, the self, and the universe, shifting the focus from external rituals to internal spirituality and understanding. While the Vedas are a collection of hymns, prayers, and rituals, the Upanishads are philosophical texts that lay the foundation for later Hindu philosophy and introduce pivotal ideas that would influence other religious traditions like Buddhism and Jainism.