There is no means of avoiding the final collapse of a boom brought about by credit expansion. The alternative is only whether the crisis should come sooner as the result of voluntary abandonment of further credit expansion, or later as a final and total catastrophe of the currency system involved.
Once you think that something is improbable and everybody thinks it, people modify their behavior in a way that makes it more probable. Everyone thought it was so improbable that so many people would default on real estate, it actually created a greater probability that it would happen because more capital flowed into that sector.
Experience, however, shows that neither a state nor a bank ever have had the unrestricted power of issuing paper money without abusing that power; in all states, therefore, the issue of paper money ought to be under some check and control; and none seems so proper for that purpose as that of subjecting the issuers of paper money to the obligation of paying their notes either in gold coin or bullion.