C0: Introduction
1
Most materials in this chapter are based on materials from
https://ai.berkeley.edu
WORLD
AGENT
percepts
actions
C0
Introduction
COMP3270
Introduction to Artificial Intelligence
What Would Count as Intelligence?
What Would Count as Intelligence?
2
TASK
A
Calculator
B
Chess Engine
C
Chatbot
D
Self-Driving Car
What evidence are you using?
How Should We Judge Intelligence?
How Should We Judge Intelligence?
3
What do we evaluate?
THINKING
↔
ACTING
What is the benchmark?
HUMAN-LIKE
↔
RATIONAL
Combine the answers → four ways to define AI
Build AI That…
Build AI That…
4
HUMANLY
RATIONALLY
THINK
Think Humanly
Thinks like a human
Think Rationally
Reasons correctly
ACT
Act Humanly
Acts like a human
Act Rationally
Chooses effective actions
Which Approach Guides Each AI System?
Which Approach Guides Each AI System?
5
TASK
AI System
Approach
A hypothetical brain simulation that reproduces how humans think
A chatbot designed to convince a judge that it is human
An automated theorem prover that derives valid conclusions
A self-driving car that chooses actions to reach its destination safely
Thinking Humanly Models Human Cognition
Thinking Humanly
Models Human Cognition
6
TASK
OBSERVE
Human Thinking
Introspection · experiments · brain activity
→
MODEL
Computational Process
Turn a theory into a program
→
COMPARE
Model and People
Do they solve the task in the same way?
A person and a model give the same answer. Does that mean they thought in the same way?
Acting Humanly Tests Human-Like Behaviour
Acting Humanly
Tests Human-Like Behaviour
7
Can a judge reliably tell which response came from a person?
?
HUMAN JUDGE
↔
TEXT ONLY
HUMAN
AI
The test evaluates observable behaviour, not the hidden process
Thinking Rationally Applies Correct Reasoning
Thinking Rationally
Applies Correct Reasoning
8
TASK
All men are mortal
Socrates is a man
Therefore, Socrates is mortal
What is the limitation of this approach?
This Course Focuses on Acting Rationally
This Course Focuses on
Acting Rationally
9
DEFINITION
Choose the action expected to achieve the best outcome
Example: Acting Rationally Under Uncertainty
Example:
Acting Rationally
Under Uncertainty
10
TASK
FORECAST
70%
chance of rain
→
ACTION
☂
take an umbrella
→
OUTCOME
☀
it stays dry
Was taking the umbrella irrational?
An Agent Perceives, Decides, and Acts
An Agent Perceives, Decides, and Acts
11
An agent is anything that
perceives
its environment and
acts
upon it.
ENVIRONMENT
percepts
AGENT
actions
The loop repeats as the world changes
What Made This Choice Rational?
What Made This Choice Rational?
12
Taking the umbrella depended on four things
OBJECTIVE
Stay dry
EVIDENCE
70% chance of rain
KNOWLEDGE
An umbrella reduces the risk
ACTIONS
Take it or leave it
Rational Does Not Mean Omniscient
Rational Does Not Mean Omniscient
13
RATIONAL
≠
KNOWS THE FUTURE
Use the information available now
Choose under limited time and memory
A rational decision can still lead to a bad outcome
A Self-Driving Car With One Objective
A Self-Driving Car With One Objective
14
TASK
SELF-DRIVING CAR
Maximize safety
DESTINATION
Which behaviour receives the highest score?
A Vacuum Robot With One Objective
A Vacuum Robot With One Objective
15
TASK
VACUUM-CLEANING ROBOT
Collect as much dirt as possible
ROBOT
How could the robot maximize its score?
Specify the Performance Measure Carefully
Specify the Performance Measure Carefully
16
PERFORMANCE MEASURE
How the agent's success is scored
POOR MEASURE
Amount of dirt collected
BETTER MEASURE
Cleanliness maintained over time
ALSO CONSIDER
coverage · energy · time · safety
This Course Builds a Toolkit for Rational Action
This Course Builds a Toolkit for Rational Action
17
SEARCH
· C1
Which action sequence reaches the goal?
MDPs
· C2
Which action is best when outcomes are uncertain?
REINFORCEMENT LEARNING
· C3
How can an agent improve from experience?
PROBABILISTIC MODELS
· C4–C6
What should the agent believe from noisy evidence?
LOGIC
· C7
What follows from what the agent knows?
AI Progress Comes in Waves
AI Progress Comes in Waves
18
1950s
Logic and Search
1970s–80s
Expert Systems
1990s–2000s
Probability and Data
2010s
Deep Learning
2020s
Generative and Agentic AI
Each wave solves some problems and reveals new limitations
The Thinking Machine, 1961
The Thinking Machine, 1961
19
TASK
What stands out about the way they describe intelligent machines?
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