On the Nochka-Chen-Ru-Wong Proof of Cartan's Conjecture

In 1982-83, E. Nochka proved a conjecture of Cartan on defects of holomorphic curves in ${\mathbb{P}}^n$ relative to a possibly degenerate set of hyperplanes. This was further explained by W. Chen in his 1987 thesis, and subseqently simplified by M. Ru and P.-M. Wong in 1991. The proof involved assigning weights to the hyperplanes. This paper provides a mild simplification of the proof of the construction of the weights, by construing the ``Nochka diagram’’ of Ru and Wong as a convex hull.