Date: Oct 17, 2012 1:37 PM
Author: kirby urner
Subject: Re: In favor of teaching "dot notation"

On Wed, Oct 17, 2012 at 6:57 AM, Joe Niederberger <>
> Kirby says:
>>Lots of interesting musings and speculations, but I see nothing there to
dissuade us from sharing more widely and effectively what 21st century math
notations include
> Functional or "to one" relationships are pretty well understood today, no

need to imbue them with mystical powers of action, or connotations of
"belonging to" or "contained within". By the way, which is it? "Belong to"?
or "contained in", or yet more? Is "dot" a superverb?
> Joe N

The skill we want to encourage in students is the ability to look out over
a vista, be it physical and/or conceptual, and break it down into "objects".

People will see "break it down" as "reductionism" and I can't fight the
etymological links between "break down" and "reduce" so I guess they're

A classic "object" would be an atom. We can unify with chemistry by going:

Br.s Ba.s

to refer to the s orbitals of Bromine and Barium respectively.

Lets change frequencies and look at a more macro world instead: tractors
plow, plant and help harvest (by pulling other devices) and food flows to
market and overflow in city centers. Problem: revectoring overflow to
serving centers via quality control, storage, prepping and cooking, serving.

That's a story problem I've proposed on the Math 2.0 listserv (Google
group) a few times, in different ways.

Lets start with the Tractor, a blueprint / template (open source) of which
many instances plow the fields. So each tractor has gps coordinates, lat /
long, and a timeline (snap shots of lat/longs past), and a fuel level.

thistractor = Tractor()
thistractor.fuel = 10 # filled on Oct 13

thistractor.moveto("FieldA start") # a lookup table provides lat/log
thistractor.plow() # a routine kicks in,
already programmed w/r to a field (see API)

and so on. William Kent says warehouse inventory is a game that modeling
languages might indeed play accurately and with gusto. It's when you zoom
out and include more players that you get into trouble. Keep your language
games simple and discrete. Divide responsibility. We agree. That doesn't
destroy the big picture because you, the architect of this system, need to
keep all the agents in view (you're like some "overseer" of your "energy
slaves" **).

On the city side, you have these cargo bike trailers, some hand made. The
bike is a lot like the tractor in the field in having lat/long. It's human
powered, so the "fuel level" has to do with said human spending calories.
Fortunately, said human has access to "servings" (a "tank up" station in
tractor terms) so will be "renewable" in our model.

Are we outside what a Kent model could handle? I don't know yet. Maybe
not. In any case, in the real world we have:

cycle12.moveto("SDW") # a church, a real one, you can check my data
(St. David of Wales, 28th and Harrison, use Google Earth)
cycle12.trailer.unload(satmart) # so like a verb, where satmart is it's
own object: that which was retrieved from Saturday markets

You're probably thinking "turtle graphics" i.e. our cycle and tractor
objects seem a lot like Seymour Papert style turtles. No question about
it. Very much so.

Note that cycle12 is pulling a trailer, an object in itself. SkyBlue is
one of ours, parked at my seFnb.bluehouse i.e. my household belongs in the
Southeast Portland Food Not Bombs chapter. This is true. Bishop & Milgrim
are free to look. I'm the math teacher. This is math. Washington High
School. OPDX. It's all transparent.

Anyway, that's how dot notation really works in the real world. We have
machines that know it, virtual machines. They control YouTube, work at
Google, have all the best jobs in the universe (not talking about humans,
talking about languages). If you want to work in that kind of
infrastructure, where Java, C++ and Python are used (that's today, always
changing), then of course you need to know dot notation, no question. All
of the above are dot notation languages. Objective C is proudly in another
camp, and that's fine. I'm not saying dot notation is god or the be all
end all. I'm saying here's another notation that STEM math introduces, but
that 1900s math does not. Vote with your feet. I predict zero jobs for
the 1900s illiterate. But that's just me (here today, gone tomorrow).



Message was edited by: kirby urner