Lesson 2
1. Lesson 2
1.7. Lesson 2 Summary
Module 2: Logic and Geometry
Lesson 2 Summary

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Every day, people make predictions and generalizations based on patterns. They may make observations of a pattern while playing a game, solving a puzzle, or while watching a particular situation. When specific observations are used to make general conclusions or conjectures about a situation, inductive reasoning is being used.
For instance, an adult couple that observes a few video game stores full of teens may make the statement that all teens like video games. Their conjecture is based on observations of the clientele in video game stores. The conjecture may be strengthened by observations of more teens playing video games or other game stores full of teens.
As you have seen in Lesson 2, the more evidence gathered to support a conjecture, the stronger the conjecture. The conjecture can be invalidated by finding one counterexample: it is possible to find one teen that doesn’t like video games. Because it is impossible to ask all teens whether they like video games, it is not possible to prove the conjecture “all teens like video games.”
Conjectures can be revised based on new evidence or counterexamples. Adapting conjectures based on observations is one way of revising strategies for successfully winning a game or solving a puzzle.
In Lesson 3 you will investigate what has to happen to prove a conjecture.