By saying "no clapping is possible without two hands to do it," Vivekananda is illustrating the importance of cooperation and unity. Just as two hands are needed to clap, so too are different people and groups needed to work together in order to achieve something great. This message of unity and cooperation is often used to encourage people to come together and work for the common good.
In the context of India's struggle for independence from British rule, Vivekananda's words were a powerful call for unity among Indians. He urged them to set aside their differences and work together to achieve their common goal of freedom. His message was influential in inspiring Indians to come together and fight for their independence, and it continues to be a source of inspiration for people around the world who are working for change.