The Rules...

If I like it; it's mine.

If it's in my mouth; it's mine. 

If I can take it from you; it's mine.

If I had it a little while ago; it's mine.

If I'm chewing something up; all the pieces are mine.

If it's mine; it must never appear to be yours anyway.

If it just looks like mine; it's mine.

If I saw it first; it's mine.

If you are playing with something and you put it down: it automatically becomes mine.

If it's broken; it's yours.