of crypto - assets can therefore depend on the underlying blockchains to avoid double spending and validate ownership. however, trust isn ’ t entirely dispensable. in fact, users place their trust in the opaqueness of the arrangements through which influence is dispersed across the blockchain. public blockchains still rely on key players to perform certain tasks, but these players are often unidentified and unaccountable. a protocol has to be created, maintained and operated, while the transactions it supports need to be validated. developers and miners perform actions that affect the outcome of public blockchains. furthermore, the practical usability of crypto - assets relies to a great extent on identifiable intermediaries to act as “ gateways ” between the crypto - asset ecosystem on the one hand and the financial markets and the economy on the other. i have said before that we need to differentiate between “ assets ” such as bitcoin and the technology behind them, such as blockchain. indeed, some of the technology is worth exploring 1 / 3 bis central bankers'speeches and could also be of interest to central banks. that said, our role is not to drive technological adoption by the industry and the general public, but to ensure that changing preferences can be satisfied in a secure way. while dlt is a necessary element of crypto - assets, it is not in itself their defining feature. 3 the single distinguishing feature of crypto - assets such as bitcoin is the absence of an underlying claim, which makes it difficult for them to maintain price stability. crucially, crypto - assets aren ’ t backed by any sovereign authority and, unlike financial instruments, they don ’ t give their holders ownership or contractual rights. central banks provide confidence in money – as a store of value, unit of account and means of payment – by safeguarding the stability of the currency. by contrast with traditional currencies, bitcoin has been highly volatile over the past two years. bitcoin ’ s average volatility in that period was close to 80 %, while many other crypto - assets showed even higher levels of volatility. this makes it impossible to use crypto - assets for anything but outright speculation. some crypto - assets have recently emerged that strive to minimise fluctuations in value against a currency of reference, but even they are no alternative to the euro. these so - called “ stablecoins ” broadly fall into two categories :

yves mersch : back to stable speech by mr yves mersch, member of the executive board of the european central bank, at the zahlungsverkehrssymposium, deutsche bundesbank, frankfurt am main, 29 may 2019. * * * the primary objective of the ecb is to ensure price stability. this is also the best contribution we can make to achieving sustainable growth. 1 since the launch of the euro, the ecb has delivered on this commitment and rendered price stability a reality, maintaining an average inflation rate of below, but close to, 2 %. and that is why the majority of euro area citizens trust the euro. 2 their trust is contingent on the independence of the central bank. independence is granted to central banks to prevent politicians from seeking electoral gain through measures which boost economic activity in the short term but damage the long - term health of the economy and the country. it is also recognised that legal tender needs to be issued by a public authority. in the case of the eu, it falls to the ecb to issue the euro and decide on the denomination of banknotes. we could not accept a situation in which, for anti - european or populist motives, certain euro denominations were not allowed to be used in some parts of the eu. this established consensus is being challenged by private initiatives triggered by technical innovation. we are seeing ever more solutions in search of a problem. bitcoin and other crypto - assets claim to need neither trust nor the backing of a sovereign. they reject the paradigm of state - supported currencies governed by central banks, along with the role of financial institutions as trusted intermediaries. these self - proclaimed currencies, more accurately described as crypto - assets, have proved to be unfit for purpose, demonstrating that well - executed central bank policies are still the only sound basis for stability. trustless is pointless the original bitcoin vision replaces trust in a dedicated intermediary with cryptographic proof. in other words, any two parties can transact directly with each other as peers without requiring a trusted third party. their transactions rely on distributed ledger technology ( dlt ), sometimes floridly referred to as the “ trust engine ” of crypto - assets. by leveraging cryptography and mechanisms to reach consensus among peers in a distributed system, dlt ensures the integrity and security of records which, in a centralised system, would be entrusted to a responsible third party. users