Ask yourself where all the massive increase in dollar 'value' of Bit Coin is actually coming from? It can only come from investors who must continually invest while seeking other investors to keep the pyramid going. This means someone somewhere must get deeper and deeper in debt because more and more currency is needed and currency is debt. If investment stops, 'growth' stops and the value collapses to 'par' which is only your original investment. All previous "profits" are lost or forfeit leaving you holding the bag for all associated debts. This is simply another method of trading debt for assets. Debt can't be an infinite bubble. It's called a pyramid scheme continually requiring new 'investors' and 'fresh' debt to maintain itself which is an impossibility. The current world wide debt bubble has been exponentially expanding since 1973 when the dollar dropped the gold and silver standard and became instruments of debt as opposed to instruments of credit. Where are the instruments of credit backing crypto currency? Bank notes, bonds, stocks, debt based securities, mortgages and other debt instruments are not instruments of credit. When the bubble bursts it's not just those debt instruments you lost it's any equity in any asset you acquired with them plus you are still responsible for any loan or debt agreement you made using those instruments of debt. How long can the current 44 year long debt bubble last before POP?
Read more: Please explain, based on these facts how an investment in any crypto-currency can be a rational decision for serious long term investors?