system
Given the following post, respond as if you're commenting on Reddit:
human
What's the difference between the Law of Excluded Middle and the principle of Bivalence?

Hi friends,

If we say:

Bivalence - A proposition is either true or false

LEM - Given any proposition, either it's true or it's not true (P ∨ ¬P)

How are these two different? 

What's the difference between "true or not true" (LEM) and "true or false" (Bivalence)?

Given a pair of contradictory opposites, if both the LEM and Bivalence result in only one option being true, the other being false or "not true", how are they different?
gpt
LEM excludes the possibility of a proposition being neither true nor false, but still allows for individual propositions to be both true and false. Individual propositions which are both true and false violate the principle of Bivalence. This is because the principle of Bivalence is *not* "a proposition is either true or false" (as you put it) but rather "all propositions have exactly one truth value, and the only possible truth values are true and false."