OCCUPY SAMIZDAT: Basic Effing Logic 101: Unions, and Intersections

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Now, in the spirit of, one must first know the rules to break them, and also; Bob's Quick Guide to the Apostrophe, You Idiots. Let's begin...

At school, this is probably taught quickly squeezed in between trigonometry, and calculus along with boolean algebra

When really it is so easy.... So simple that it should be taught around the same time they are teaching you that 1+1=2.

If you learnt it at school you probably got taught it using all sorts of noodly things such as set theory and the slightly less scary venn diagram.

There's a simpler way to understand unions and intersections.

First

Take your left hand, raise one finger and make it a forward slash

Like: /

Second

Take your right hand, raise one finger and... take a wild guess

That's right a backward slash: \


Ok


Now, cross the two fingers so they form a cross

Which should look like an X

The point where the two fingers cross is the intersection

The combination of the two fingers forming an X is the union of your left finger forming a / and your right finger forming an \

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Ok, at this point if you have a piece of paper and some pens handy we're in for a bit of fun

First draw a forward slash /

Then draw a back slash \

Label one, theory

Label the other, practice

now draw an X

Circle the intersection

Circle around the whole X to circle the union

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Experiment, draw a bunch of lines crossing each other, then circle the intersections

Finally circle the union