Cs3014: Artificial Intelligence introduction to artificial intelligence

Systems that act like humans

• These cognitive tasks include:
• Natural language processing
• for communication with human
• Knowledge representation
• to store information effectively & efficiently
• Automated reasoning
• to retrieve & answer questions using the stored information
• Machine learning
• to adapt to new circumstances

The total Turing Test

• Includes two more issues:
• Computer vision
• to perceive objects (seeing)
• Robotics
• to move objects (acting)

Systems that think like humans: cognitive modeling

• Humans as observed from ‘inside’
• How do we know how humans think?
• Introspection vs. psychological experiments
• Cognitive Science
• “The exciting new effort to make computers think … machines with minds in the full and literal sense” (Haugeland)
• “[The automation of] activities that we associate with human thinking, activities such as decision-making, problem solving, learning …” (Bellman)

Systems that think ‘rationally’ "laws of thought"

• Humans are not always ‘rational’
• Rational - defined in terms of logic?
• Logic can’t express everything (e.g. uncertainty)
• Logical approach is often not feasible in terms of computation time (needs ‘guidance’)
• “The study of mental facilities through the use of computational models” (Charniak and McDermott)
• “The study of the computations that make it possible to perceive, reason, and act” (Winston)

Systems that act rationally: “Rational agent”

• Rational behavior: doing the right thing
• The right thing: that which is expected to maximize goal achievement, given the available information
• Giving answers to questions is ‘acting’.
• I don't care whether a system:
• replicates human thought processes
• makes the same decisions as humans
• uses purely logical reasoning