The most important reason for Hinduism to survive in spite of being made to face an unending cascade of attacks and intrusions and military occupations is that it has no centralized structure. The special characteristic feature of Hinduism is its ability to face tension, to have tolerance, to compromise and to keep up the spirit of accommodation and absorption. Indra, Varuna, Vayu, Agni, Mitra and others were the chief gods of the Vedic Hinduism. The Rig Veda criticized the practice of the worshipping of phallus. But when Hinduism evolved over a period of time, the Vedic gods were thrown out, and prominence was given to Vishnu and Shiva. Hinduism showed the vision to absorb the customs, practices and rituals of the non-Aryans also. And as the borderline between the north of India and the south blurred and disappeared, a new Hinduism of more internal independence took shape.  Along with hierarchical and caste-based traditions, customs and doctrines of wider perspectives became acceptable. And mutually contradictory doctrines and dissenting voices became natural additions to the philosophical body of Hinduism.