Fourth PLN Reflection

I was first exposed to Keith Devlin when Professor Tocci gave me this PDF, an except from Paul Lockhart's A Mathematician's Lament, the introduction to which Dr. Devlin wrote. 

Devlin is National Public Radio's math contributor.

His twitter feed from the past couple of days has been kind of interesting.  I'll isolate two links in particular.  First, he posted a CNN article of which he said, "This is what you get when you elect innumerate people to Congress. They fail Econ 101 and Finance 101 as well." The article examines the problems with "Cut, Cap, and Balance."  CNN argues that the plan distracts from the need to raise the debt ceiling, cuts spending in the middle of a recession which would just further depress the economy, is too vague on what to cut and too demanding in making cuts to a budget comprised of things that are either deemed non-negotiable (defense) OR very politically popular (Social Security, Medicare), and is unwilling to consider increased taxes as a solution.

The tweet is a powerful illustration because it involves a professional mathematician pointing out what happens when policy makers attempt to ignore the rules of mathematics.  Moreover, the particular policy in question is very relevant to our Democracy.  In that regard, it is exactly the kind of example that teacher should use to motivate the math. 

Second, he tweeted his write up on multiplication, in which he fervently distinguishes multiplication from repeated addition.  He isolates several problems with thinking about multiplication in this way.  The details are probably interesting only to math teachers.  Nonetheless, the combination of these two articles yet again illustrates the power of Twitter to find random, classroom applicable tidbits.