2012-11-27

Mathematical tools – Part 2

Were it not for convoluted language, plenty of lawyers would be out of work.  Educators, though, shouldn't be subjected to such torture.

William McCallum, one of CCSSI’s authors, wrote in the comments section of an article appearing on The Atlantic Magazine website, written by Barry Garelick, ``I agree with you that there is a lot of misreading of the standards out there in the field, and this is a problem.’’  Such arrogance.  The real problem is that CCSSI is poorly written, not only substantively, but also in its lack of clarity.

7.G.2’s ``Focus on constructing triangles from three measures of angles or sides...‘’ is at best, ambiguous.  Writing intelligible English is not the same as constructing logic gates, where the definition of ``or’’ invariably includes the possibility of both.  The parallelism in the sentence implies you are given either 3 angles or 3 sides, but we suspect it’s supposed to mean the following: ``Focus on constructing triangles given various combinations of three angles and/or sides.’’

2012-11-12

Mathematical tools – Part 1

CCSSI 7.G.2 states, ``Draw (freehand, with ruler and protractor, and with technology) geometric shapes with given conditions. Focus on constructing triangles from three measures of angles or sides, noticing when the conditions determine a unique triangle, more than one triangle, or no triangle.’’

Some preliminaries before we parse this standard.

Protractors


We here at ccssimath.blogspot.com LOVE protractors.  The way we see it, a (non-toxic, teething) protractor should be given to every newborn in their bassinet (thanks to Charles Schulz for the inspiration); perhaps the first one can be hanging from a mobile.  A protractor (like a banjo) is a happy thing: it’s a smile, or a big letter D.  A protractor is easy to hold, it’s too big to choke on, and it’s covered with numbers.  It even has mystery and intrigue, for why would the numbers run in opposite directions?  Rulers, in contrast, though useful, are dangerous things; they fit in the mouth and can be brandished as swords.

2012-10-12

Dodgy beginnings

In legal argument, every assertion cites authority: when lawyers know they are losing, they attempt to cloak weak arguments in language such as ``it is clear that’’, glossing over the insufficient basis for why; strong assertions cite controlling authority, such as a prior ruling of the U.S. Supreme Court.  The same citation requirements hold true for judicial opinions.  The American common law system is grounded in its constitutions and legislation, but also on the principle of stare decisis, which means a strong legal opinion will cite another, preferably higher, controlling authority for coming down on one side or another.  In the absence of binding authority, non-binding or persuasive authority is relied on: someone made an argument that won a case in another jurisdiction, the judge cites that decision and the law expands to a new jurisdiction.  Opponents of such decisions with weak legal precedent may deride them as ``judicial activism’’, but judge-made law is a fundamental component of how our system works, and indeed, how the legal system has managed to survive.  Of course, a judge may instead reject another non-controlling decision and cite an alternative argument for ruling differently.  Thus, competing legal doctrines scatter like leaves in the wind until a higher court decides to consolidate and resolve contradictory rulings.  It is often possible (and enlightening) to trace a winning argument in a high court ruling down through various lower court decisions and ultimately arrive at the original language source, which can be the unprecedented argument of a jurist publishing research (and personal opinions) in some obscure law journal.  Thus judge-made law, sometimes with questionable origins, becomes the law of the land and not always for the better.