Kusaka Gensui

To lament the teacher’s sad life is profitless.
The important thing is not to let the teacher’s intentions falter.

– Kusaka Genzui to a fellow student of the Sonjuku after the death of Yoshida Shoin

The majority of this information is taken from the following work:
Thomas M. Huber. The Revolutionary Origins of Modern Japan — Stanford Unviersity Press, 1981