John McCarthy
The creator of Lisp and arguably the father of modern artificial intelligence, John McCarthy, died the 23rd of October 2011. John McCarthy was born in Boston, Massachusetts on September 4, 1927 to an Irish immigrant father and a Lithuanian Jewish immigrant mother, John Patrick and Ida Glatt McCarthy. The family was forced to move frequently during the Depression, until McCarthy's father found work as an organizer for the Amalgamated Clothing Workers in Los Angeles, California.
McCarthy was reportedly expelled from Caltech for failure to attend physical education courses; he then served in the US Army and was readmitted, receiving a B.S. in Mathematics in 1948. It was at Caltech that he attended a lecture by John Von Neumann that inspired his future endeavors. McCarthy initially continued his studies at Caltech. He received a Ph.D. in Mathematics from Princeton University in 1951 under Solomon Lefschetz. He studied mathematics with the famous John Nash at Princeton and, notably, held the first “computer-chess” match between scientists in the US and the USSR. He transmitted the moves by telegraph.
McCarthy believed AI should be interactive, allowing for a give and take similar to AI simulators like Eliza and, more recently, Siri. His own labs were run in an open, free-wheeling fashion, encouraging exploration and argument. He won the Turing Award from the Association for Computing Machinery in 1972 and the National Medal of Science in 1991. McCarthy believed AI should be interactive, allowing for a give and take similar to AI simulators like Eliza and, more recently, Siri. His own labs were run in an open, free-wheeling fashion, encouraging exploration and argument. He won the Turing Award from the Association for Computing Machinery in 1971, the Kyoto Prize in 1988, the National Medal of Science in 1991, inducted as a Fellow of the Computer History Museum in 1999, Benjamin Franklin Medal in Computer and Cognitive Science from the Franklin Institute in 2003, and Inducted into IEEE Intelligent Systems' AI's Hall of Fame in 2011, for the "significant contributions to the field of AI and intelligent systems".
LISP
LISP stands for List Processing.
In 1958 John McCarthy took a summer position at the IBM Information Research Department. He was hired to create a set of requirements for doing symbolic computation. The first attempt at this was differentiation of algebraic expressions. This initial experiment produced a list of language requirements, most notably was recursion and conditional expressions. At the time, not even FORTRAN (the only high-level language in existence) had these functions.
- Atoms & Lists - Lisp uses two different types of data structures, atoms and lists.
- Atoms are similar to identifiers, but can also be numeric constants
- Lists can be lists of atoms, lists, or any combination of the two
- Functional Programming Style - all computation is performed by applying functions to arguments. Variable declarations are rarely used.
- Uniform Representation of Data and Code - example: the list (A B C D)
- a list of four elements (interpreted as data)
- is the application of the function named A to the three parameters B, C, and D (interpreted as code)
- Reliance on Recursion - a strong reliance on recursion has allowed Lisp to be successful in many areas, including Artificial Intelligence.
- Garbage Collection - Lisp has built-in garbage collection, so programmers do not need to explicitly free dynamically allocated memory.
Lisp totally dominated Artificial Intelligence applications for a quarter of a century, and is still the most widely used language for AI. In addition to its success in AI, Lisp pioneered the process of Functional Programming. Many programming language researchers believe that functional programming is a much better approach to software development, than the use of Imperative Languages (Pascal, C++, etc.).
Below is a short list of the areas where Lisp has been used:
Below is a short list of the areas where Lisp has been used:
- Artificial Intelligence
- AI Robots
- Computer Games (Craps, Connect-4, Black Jack)
- Pattern Recognition
- Air Defense Systems
- Implementation of Real-Time, embedded Knowledge-Based Systems
- List Handling and Processing
- Tree Traversal (Breath/Depth First Search)
- Educational Purposes (Functional Style Programming)
