Background
Greenblatt was born in Portland, Oregon on December 25, 1944. He later moved to Columbia, Missouri with his mother and sister when his parents divorced.
Greenblatt was born in Portland, Oregon on December 25, 1944. He later moved to Columbia, Missouri with his mother and sister when his parents divorced.
Massachusetts Institute of Technology.
Along with Bill Gosper, he may be considered to have founded the hacker community, and holds a place of distinction in the Lisp and the Massachusetts Institute of Technology Artificial Intelligence Laboratory communities. His family moved to Philadelphia, Pennsylvania when he was a child. Greenblatt enrolled in Massachusetts Institute of Technology in the fall of 1962, and around his second term as an undergraduate student, he found his way to Massachusetts Institute of Technology"s famous Technical Model Railroad Club.
At that time, Peter Samson had written a program in Fortran for the International Business Machines Corporation 709 series machines, to automate the tedious business of writing the intricate timetables for the Railroad Club"s vast model train layout.
Greenblatt felt compelled to implement a Fortran compiler for the PDP-1, which did not have one at the time. There was no computer time available to debug the compiler, or even to type it into the computer.
Years later, elements of this compiler (combined with some ideas from fellow TMRC member Steven Piner, the author of a very early PDP-4 Fortran compiler while working for Digital Equipment Corporation) were typed in and "showed signs of life". However, the perceived need for a Fortran compiler had evaporated by then, so the compiler was not pursued further.
Indeed, he spent so much time programming the PDP machines there he failed out of Massachusetts Institute of Technology as a first-term junior and had to take a job at the Charles Adams Associates firm until the Artificial Intelligence Laboratory hired him about 6 months later.
He was the main implementor of Maclisp on the PDP-6. He wrote Mac Hack, the first computer program to play tournament-level chess and the first to compete in a human chess tournament. Artificial Intelligence skeptic Hubert Dreyfus, who famously made the claim that computers would not be able to play high-quality chess, was beaten by the program, marking the beginning of "respectable" computer chess performances.
Greenblatt, along with Tom Knight and Stewart Nelson, co-wrote the Incompatible Timesharing System, a highly influential timesharing operating system for the PDP-6 and PDP-10 used at Massachusetts Institute of Technology.
Later, he and Tom Knight were the main designers of the Massachusetts Institute of Technology Lisp machine.
He founded (which later became Gigamos Systems), according to his vision of an ideal hacker-friendly computer company, as opposed to the more commercial ideals of Symbolics.