All vs. Some

I wish people of all ethnicities would learn the meaning of ALL and SOME. All white cops aren’t racist pigs, and all black people are not thugs. In mathematics we use lots of symbols as a shorthand way of writing statements.

One of the symbols, ∀, means “for every,” “for each,” “for all.”

Another symbol, ∃, means “there exist(s),” or “there is at least one,” or “there are some.”

The symbol, ≠, means “is not equal to.”

Another symbol is ~, which means “it is not the case that” or “it is not true that.”

Another symbol, ∋, means “such that.”

For instance, if I say let x represent “a white police officer” and let y represent “racist.” Then I could make the statement: ∀x, x = y. (That reads, for EVERY white police officer, that police officer is racist.) That statement is FALSE, and we know it. But if I say:
∃x ∋ x=y (which reads there exist, or there are some white police officers such that those officers are racist.) That is a TRUE statement. I could write: ∃x ∋ x= ~y OR ∃x ∋ x≠y. (There exist white police officers such that those white police officers are not racist.) that is a TRUE statement.

Then I could say change it up and let x represent “black people” and let y represent “thugs.” I could use the same symbols to make the same three statements and they would still be false, true, and true…in that order.

I wish people of all ethnicities would learn the meaning of ∀ and ∃.

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