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Topic: Inclusive and exclusive definitions... again!
Replies: 17   Last Post: Mar 29, 2010 10:12 PM

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Joe Niederberger

Posts: 4,657
Registered: 10/12/08
Re: Inclusive and exclusive definitions... again!
Posted: Mar 24, 2010 10:56 PM
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My son's texbook mostly uses inclusion -
that seems "natural" to me and always has,
its the way I was taught. One exception
is "kite" versus "rhombus".

Now why would that exception be made?

Perhaps answering that question is as important
as the rest. And being flexible enough to see that
different defnitions could be made and everything
still works out fine. What are the considerations in
leaning one way versus another? My son can entertain
those sorts of thoughts. Once that stage is reached,
its of far lesser concern what road is actually taken.

Also, Venn Diagrams of course are indispensible here.

Joe N.

- ----- Original Message -----
From: "Robert Hansen" <>
To: <>
Sent: Monday, March 15, 2010 4:33 PM
Subject: Re: Inclusive and exclusive definitions... again!

> It is a coincidence that my son is working with this exact situation. I
provided some inclusion (and he is getting it) but not too heavy. Generally
though, with many of these things, exclusion applies. We can technically
gather up everything and build a tree but I find that in a natural setting
one thinks more often in an exclusive fashion because it partitions and
balances the knowledge more effectively. It's all the leaves gathered on
each of the branches that we work with. Not so much the bare tree.

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