I think wild market swings have been happening as long as markets have been around. I don't necessarily see the connection between HFT and those swings. Here's

I think wild market swings have been happening as long as markets have been around. I don't necessarily see the connection between HFT and those swings. Here's a thought: If you assume that swings are going to happen regardless of HFT, then is it possible that HFT actually helps find the real "fair value" level in the market faster than if those player's did not exist? Another thought on HFT's value to society: I generally agree that HFT does not provide "direct" value. There are clearly "arbitrage" opportunities that HFT firms consistently profit from. However, by definition, those arb opportunities will either be taken by someone else, or enough people will run into grab them such that the arb goes to zero. If there are consistent arb opportunities then something needs to change - namely the regulation which structures the market and allows people to take consistent advantage of it. Thus new regulation is issued and the market, inherently a complex and intricate system, becomes stronger as a result. This is maybe where the value to society lies. and maybe this is an idealistic view of how regulation, society and HFT interact in this case.... ?