Lowell Hawkinson passed away at the age of 74 on December 28, 2017 as a result of an accident. Lowell was a pioneer in LISP implementation and artificial intelligence. He co-founded Gensym Corporation in 1986 and served as its CEO through 2006. This obituary gives more details of his life and accomplishments.
I first got in touch with Lowell in 2010 because of my interest in archiving LISP history. We exchanged emails (and one phone conversation), and over the years I wrote several blog posts and a journal article about work involving him:
The First International LISP Conference (1963)
Harold V. McIntosh and his students: Lisp escapes MIT
The LISP 2 Project
Although my interactions with Lowell were brief, his kindness and modesty were manifest. He will be deeply missed by his family and friends.