I like the fact that this article identifies that finance serves a purpose, that it can do a lot of good. At the same time, it also recognizes that not all finance is useful or good from a societal point of view. This distinction always seems to get lost in the arguments that result when articles like this are posted on HN.

Take HFT, the perennial point of controversy. It is true that it provides liquidity (though, I would suggest not necessarily when you need it), but is it true that more liquidity is always better? At some point, I would argue that the market is liquid enough, and continually pushing the limits of HFT is quite simply rent seeking and may have other detrimental market and/or societal effects. To bring my comment back to the article in question, I have to agree with the author that it is somewhat sad to see people pursue careers in fields of dubious societal value, but if I were offered the paycheque, I would almost certainly take it, too.