Hilbert Problem 15 required an understanding of Schubert’s book [1], both its methods and its results. In this paper, following his idea, we prove that the formulas in §6, §7, §10, about the incidence of points, lines and planes, are all correct. As an application, we prove formulas 8 and 9 in §12, which are frequently used in his book.

中文翻译：

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理解舒伯特的书（一）

希尔伯特问题 15 需要理解舒伯特的书 [1]，包括方法和结果。在本文中，我们按照他的想法，证明§6、§7、§10中关于点、线和面的重合度的公式都是正确的。作为应用，我们证明了§12 中的公式 8 和 9，这在他的书中经常使用。