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I’m going to attempt to explain math (this is funny because I suck at it 😄).

Propostion #

A proposition is a factual sentence that is either true or false but can’t be both.

This is very different from how we tend to use it in our day to day lives. A propisition (in logic) is not a suggested course of action or a type of belief. So “I have a proposition: let’s buy 40 capybaras instead” is not a proposition and neither is “the proposition that every citizen deserves a free capyabara is absurd”.

Here’s a few examples of propositions:

Here are examples of statements that aren’t propositions:

Can you explain why the first list are propositins and the second aren’t?

A proposition variable is a letter that represents a propostion. For example: p could stand for “John is 29 years old”. Common proposition variables are p, q, r, s, t and v. Stringing multiple propositions together creates a compound proposition.

Let’s say p stands for “Ayisha owns two capybaras”. How would you negate this? You could say “Ayisha does not own two capybaras”. Using our variable p, it is ¬p. ¬ is a negation sign. Slap it in front of any proposition and it will flip the meaning of the proposition.

Conjuntion #

A conjuntion is two statements together where both statements are true. The symbol is ^.

An example: She owns 40 capybaras and she also owns 30 llamas.

Dysjunction ⊕ #

A dysjunction is two statements where at least one of the statements is true. The symbol is v.

An example: She has 40 million dollars or she’s a part of the mob

There are two types of or, an inclusive or and an exclusive or. In an inclusive or, one of the statements must be true. In an exclusive or, only one statement can be true.

Here’s an example of an exclusive or: You can purchase a capybara or a dog but you cannot have both.

Here’s an example of an inclusive or: Those who’ve successfully drank 70 shots of espresso or did 80 jumping jacks may recieve a free capybara.

To figure out whether a sentence is inclusive or exclusive, ask yourself “is it possible for both to be true?”.

Let’s take this ask: “Do you want a capybara or a vanilla latte?”. If you respond “I want both” and the asker is ok with that than the ask was an inclusive or.