Some 19th-century theologians thought that various pre-Christian religions and philosophies were pantheistic. They thought Pantheism was similar to the ancient Hindu philosophy of Advaita (non-dualism) to the extent that the 19th-century German Sanskritist Theodore Goldstücker remarked that Spinoza's thought was "... a western system of philosophy which occupies a foremost rank amongst the philosophies of all nations and ages, and which is so exact a representation of the ideas of the Vedanta, that we might have suspected its founder to have borrowed the fundamental principles of his system from the Hindus."