AI · Theory

Simple Reflex Agent

Theory

190/215

Simple Reflex Agent

Simple reflex: if percept then action. No memory of the past. Thermostat: if temp < 20 then heat. Vacuum: if dirt then suck else move. Fails when the right action depends on history (a maze).

Upgrade path — add internal state (model-based). Don’t call a huge LLM a simple reflex.

Simple Reflex Agent — output — heat off. No memory of yesterday.

Diagram

sensors  →  agent  →  actuators
                │
                ▼
            environment

Exam tip

Thermostat example + when it fails.

Example

# Thermostat reflex
def reflex(temp):
    return "heat" if temp < 20 else "off"

print(reflex(18), reflex(22))

Simple Reflex Agent — output: heat off. No memory of yesterday.

Short notes

DefCondition–action rules. No memory.
RuleFails when history matters.

AI · Theory

Simple Reflex Agent

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Theory

190/215

Simple Reflex Agent

Simple reflex: if percept then action. No memory of the past. Thermostat: if temp < 20 then heat. Vacuum: if dirt then suck else move. Fails when the right action depends on history (a maze).

Upgrade path — add internal state (model-based). Don’t call a huge LLM a simple reflex.

Simple Reflex Agent — output — heat off. No memory of yesterday.

Diagram

sensors  →  agent  →  actuators
                │
                ▼
            environment

Exam tip

Thermostat example + when it fails.

Example

# Thermostat reflex
def reflex(temp):
    return "heat" if temp < 20 else "off"

print(reflex(18), reflex(22))

Simple Reflex Agent — output: heat off. No memory of yesterday.

Short notes

DefCondition–action rules. No memory.
RuleFails when history matters.

Simple Reflex Agent

Example

Short notes

Questions

Simple Reflex Agent

Example

Short notes

Questions