Jonathan Crabtree posted Jan 7, 2013 12:07 PM: > Re: "teaching fractions with paper folding" > > Multiply is from the Latin multiplicare. Plicare is > Latin for fold. Multi means many. > > This is also how we get the word manifold, as in > twofold, threefold, fourfold and manifold increase. > > Whether folding or unfolding, complex or simplex, the > folding idea as a model has been around for a tad > moer than 25 years now. > > "Those who cannot remember the past are condemned to > repeat it." > > Jonathan Crabtree > P.S. Crumple paper and you multiply it. Why? You find > it in creases. > Interesting and useful! I was vaguely 'aware' of 'plicare' and 'multi' - but I had never put them together!