 Logic was introduced into AI research as early as 1958 , by John McCarthy in his Advice Taker proposal . In 1963 , J. Alan Robinson had discovered a simple method to implement deduction on computers , the resolution and unification algorithm . However , straightforward implementations , like those attempted by McCarthy and his students in the late 60s , were especially intractable : the programs required astronomical numbers of steps to prove simple theorems . A more fruitful approach to logic was developed in the 1970s by Robert Kowalski at the University of Edinburgh , and soon this led to the collaboration with French researchers Alain Colmerauer and Philippe Roussel who created the successful logic programming language Prolog . Prolog uses a subset of logic ( Horn clauses , closely related to " rules " and " production rules " ) that permit tractable computation . Rules would continue to be influential , providing a foundation for Edward Feigenbaum 's expert systems and the continuing work by Allen Newell and Herbert A. Simon that would lead to Soar and their unified theories of cognition . 
 Logic was introduced into AI research as early as 1958 , by John McCarthy in his Advice Taker proposal . In 1963 , J. Alan Robinson <a href='been_done' title='1'><mark>had</mark></a> discovered a simple method to implement deduction on computers , the resolution and unification algorithm . However , straightforward implementations , like those attempted by McCarthy and his students in the late 60s , <a href='uninflect' title='2'><mark>were</mark></a> especially intractable : the programs required astronomical numbers of steps to prove simple theorems . A more fruitful approach to logic was developed in the 1970s by Robert Kowalski at the University of Edinburgh , and soon this led to the collaboration with French researchers Alain Colmerauer and Philippe Roussel <a href='null_relcl' title='3'><mark>who</mark></a>created the successful logic programming language Prolog . Prolog <a href='uninflect' title='4'><mark>uses</mark></a> a subset of logic ( Horn clauses , closely related to " rules " and " production rules " ) <a href='null_relcl' title='5'><mark>that</mark></a>permit tractable computation . Rules would continue to be influential , providing a foundation for Edward Feigenbaum <a href='null_genetive' title='6'><mark>'s</mark></a>expert systems and the continuing work by Allen Newell and Herbert A. Simon <a href='null_relcl' title='7'><mark>that</mark></a>would lead to Soar and their unified theories of cognition . 
Logic was introduced into AI research as early as 1958 , by John McCarthy in his Advice Taker proposal . In 1963 , J. Alan Robinson done discovered a simple method to implement deduction on computers , da resolution and unification algorithm . However , straightforward implementations , like those attempted by McCarthy and his students in the late 60s , was especially intractable : the programs required astronomical numbers of steps to prove simple theorems . A more fruitful approach to logic was developed in the 1970s by Robert Kowalski at the University of Edinburgh , and soon dis led to the collaboration with French researchers Alain Colmerauer and Philippe Roussel created tdasuccessful logic programming language Prolog . Prolog use a subset of logic ( Horn clauses , closely related to " rules " and " production rules " ) permit tractable computation . Rules would continue to b influential , providing a foundation for Edward Feigenbaum  expert systems and thdaontinuing work by Allen Newell and Herbert A. Simon would lead to Soar and their unified theories of cognition .