The [ten suchnesses in Chapter 2, Expedients,] seem logical and self-explanatory. Its logic, however, is not easy for ordinary people to understand. For example, “as such” implies “as it is,” and refers to an ultimate truth which has been grasped intuitively. It is understood by a religious intuition (called prajna in Sanskrit) entirely beyond our ordinary way of understanding things as this or that. “As such” also represents reality or the ultimate truth—the way something really is, not the way we think it is. These ten perspectives are called the “Ten Suchnesses.” Chih-i of China (538-97) and Nichiren of Japan (1222-82) used them in formulating their philosophical doctrines of “each of the ten realms of existence contains the other nine in itself,” and “one thought is the three thousand worlds.”
Introduction to the Lotus Sutra