
The frequencies of the notes in a scale—do, re, mi, fa, sol, la, ti, do—sound to us like they’re rising in equal steps. But objectively their vibrational frequencies are rising by equal multiples. We perceive pitch logarithmically.
Steven Strogatz 
Change is most sluggish at the extremes precisely because the derivative is zero there.
Steven Strogatz

In mathematics, our freedom lies in the questions we ask — and in how we pursue them — but not in the answers awaiting us.
Steven Strogatz 
When you create something new, you're breaking tradition  which is an act of defiance.
Steven Strogatz 
Looking at numbers as groups of rocks may seem unusual, but actually it's as old as math itself. The word "calculate" reflects that legacy  it comes from the Latin word calculus, meaning a pebble used for counting. To enjoy working with numbers you don't have to be Einstein (German for "one stone"), but it might help to have rocks in your head.
Steven Strogatz 
Logic leaves us no choice. In that sense, math always involves both invention and discovery: we invent the concepts but discover their consequences. … in mathematics our freedom lies in the questions we ask – and in how we pursue them – but not in the answers awaiting us.
Steven Strogatz 
Those of us who teach math should try to turn this bug into a feature. We should be up front about the fact that word problems force us to make simplifying assumptions. That’s a valuable skill—it’s called mathematical modeling.
Steven Strogatz 
To grasp how different a million is from a billion, think about it like this: A million seconds is a little under two weeks; a billion seconds is about thirtytwo years.
Steven Strogatz