My comment was a direct response to the parent comment, which claimed information symmetry isn't cited as a requirement for functioning markets.
That particular statement is untrue, so I replied.
A lot of the value in things like the stock market is to disseminate the various information asymmetries in the form of price.
There's a reason guys like Paul Krugman write books on economics rather than trade the market.
EDIT: Don't take my word for it. Look at the SEC web site's description of their purpose. Excerpt (emphasis mine): "To achieve this, the SEC requires public companies to disclose meaningful financial and other information to the public. This provides a common pool of knowledge for all investors to use to judge for themselves whether to buy, sell, or hold a particular security. Only through the steady flow of timely, comprehensive, and accurate information can people make sound investment decisions."