Any belief, that is perceived to be both widely held and unchallengeable could be labelled as 'conventional wisdom'. It has become widely used amongst pundits and commentators as shorthand for what they
believe public opinion is or should be on the topic of their choice. Winds change, flavours of the month
speed by and we find the conventional wisdom of today is markedly different from that of last year. Conventional wisdom always dwells on the past
The term 'conventional wisdom' originates from the Harvard economist JK Galbraith's 1958 work The Affluent Society. Galbraith defined it ironically as "the ideas which are esteemed at any time for their acceptability". He used this idea to describe economic principles which had passed down generations, to rail against those who would stifle the questioning of these supposably a priori assumptions and the resulting consolidation of economic decision-making amongst an educated and conformist elite. It was a call for more creative thinking, a plea for greater understanding and a demand to always question your underlying assumptions.
Now the term, hijacked and transient, is used carelessly and often reveals far more about the person using it then whatever wisdom they are attempting to spread.