The recent catastrophic bubbles [of 2008] in the electricity, oil, housing, and financial markets bring home to us that the relationship between physical reality and the signs, values, and meanings we give to it can be wildly unstable….That faith has now been shaken, but there is what pundits call an upside: we are forced to reconsider the whole question of what value is, what meaning is, what the word reference itself refers to.