what is the meaning of "advance the cause" in this context?
It was in this year 1871 that Kate Fox's visit to England was brought about through the generosity of Mr. Charles F. Livermore, a prominent banker of New York, in gratitude for the consolation he had received from her wonderful powers, and to advance the cause of Spiritualism. He provided for all her needs, and thus removed any necessity for her to give professional sittings. He also arranged for her to be accompanied by a congenial woman companion.