"Around 1967 Dan Bobrow wrote a program to do algebra problems based on symbols rather than numbers"

This quote by Marvin Minsky is referring to the advancement of computer system algebra systems in the late 1960s. Dan Bobrow was a computer system researcher who wrote a program that might solve algebra issues utilizing symbols rather of numbers. This was a major advancement in the field of computer technology, as it enabled computer systems to resolve complex mathematical equations without the requirement for manual calculations. This development was a precursor to the development of more sophisticated computer system algebra systems, which are now used in a variety of fields, including engineering, finance, and physics. Bobrow's program was a significant advance in the development of computer system algebra systems, and it laid the groundwork for the advancement of more advanced systems in the future.