Consensus opinion tends to swing firmly in one direction and then the other.
For example, in the good old days of 2007 you would have been pretty hard-pressed to find many in the chemicals industry who saw anything but a mildly cyclical downturn.
But the widely-held view now - that we are facing five years of incredibly tough times, the first period of this length in the history of the business - might also not come true.
"In 1992, the same was being said but then within 12 months the industry was in recovery," said an old industry hand.
"I don't know what the macroeconomic factors might be on this occasion. If I did I could make a fortune. In 1992, it was the unexpected emergence of very strong Asian demand.
"But even if the economic news keeps getting ever-gloomier, the industry itself might make yet more adjustments to bring supply much more in line with demand."
He cited the sweeping production cutbacks that have already taken place as evidence that the will to make the necessary changes exists.
"Leveraged and private-sector companies will just not sit on their hands. In the distant past, action was slow because the industry was mainly state-owned."
These included Dow Chemical reducing operating rates to a 63% average in Q4 last year, BASF shutting down 25% of capacity in Q1and Bayer Material Science idling 300,000 tonne/year of polycarbonate (PC) capacity - again in the first quarter.
The cutbacks seem to have been more extensive than in a recession of this comparable severity - the one which occurred in the early 1980s.
"Chemical companies had no choice because raising working capital through re-financing was simply impossible," says a Singapore-based banker.
Maybe if cash flow remains constrained by ever-weaker revenues - even if the financial system is repaired - companies will face no option but to permanently shut down capacity and definitively cancel projects.
The extent of the capacity closures to date suggests that markets being brought back into balance is possible far more quickly than the doom-mongers (including myself) expect.
A few major bankruptcies might make this process very rapid indeed through closure of a large amount of a capacity in one fell-sweep.