deletions | additions       diff --git a/Lecture_7_Externalities_this_is__.md b/Lecture_7_Externalities_this_is__.md  index ce39cc4..6542225 100644  --- a/Lecture_7_Externalities_this_is__.md  +++ b/Lecture_7_Externalities_this_is__.md 
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Why are the animals that have the right to exist typically either furry or big? Does it have anything to do with fuzzy logic?  Why is pluto a dwarf planet?  http://plato.stanford.edu/entries/logic-fuzzy/  Is Ludo more than a bored game?  http://mathematica.ludibunda.ch/fuzzy-logic6.html