With its vast pantheon of gods and goddesses and its traditional reliance upon a strict caste system to organize society, Hinduism is often very difficult for people from the West to understand. As the world's third-largest religion and one of humanity's oldest, however, Hinduism is certainly worth learning about. Most Hindus agree that the many deities recognized in their religion are merely different sides of one supreme God. Even so, the Hindu worldview differs dramatically from the monotheistic belief systems of Judaism, Christianity, and Islam. The Hindu faith might be compared to a rainbow in which all possible colors are represented, but where every individual color has its own distinct place. That is, the one God is the rainbow and the thousands of individual deities are colors within the spectrum. Just as it acknowledges many aspects of divinity, perhaps more than any other religion, Hinduism cherishes the different conditions and types of humanity. As respected religious scholar James B. Robinson demonstrates, almost every kind of religious activity in the world may be found in some form somewhere in Hinduism.