The good are like one another, and friends to one another; and ... the bad, as is often said of them, are never at unity with one another or with themselves, but are passionate and restless: and that which is at variance and enmity with itself is not likely to be in union or harmony with any other thing.
Chemistry ceases to improve when one element is found from which all others are deductible. Physics ceases to progress when one force is found of which all others are manifestations. So religion ceases to progress when unity is reached, which is the case with Hinduism.