Paramārta-sāra (hereinafter referred to as PS) written by Ādiśeṣa in the 7th century CE presented a syncretism with its own unique characteristics, succeeding Bhagavad-gītā which is a model of syncretism. From the early 20th century to the early 21st century, a significant number of researchers reviewed the ideological identity of PS in various ways in relation to syncretism, as a result, PS was regarded as a text that mixed some or all of the four Hindu ideas of ‘Sāṃkhya, Advaita Vedānta, Bhedābheda Vedānta, and Vaiṣṇava theism’ generally. With few exceptions, researchers on PS analyzed PS from the perspective of ‘monocentric syncretism’, in which any one of the four ideas is the center. But, in the era of PS, syncretism existed as a genre from the beginning, and it is highly probable that PS mixed various ideas for each specific subject based on the syncretism, so it can be said that PS shows ‘multicentric syncretism’. Furthermore, because PS wants to integrate all the ideas of this world at once through ‘sarva-ātma-vāda’ (the theory that everything is Ātman), it can be said that PS shows syncretism characterized by ‘sarva- ātma-vāda’. From this, what is built in PS is an ‘independent theory of syncretism’ and a ‘syncretistic soteriology’. However, since ‘sarva-ātma-vāda’ of PS promotes a monistic or monotheistic project through the strategy of universalism, the advantage of a pluralistic and multi-valued mixture implied by the multicentric syncretism may disappear. As in the example of PS, whether to emphasize more multi-centrality or universality in syncretism is also an important issue facing current Hindu thought.