I have put both my foot and my money in my mouth. I went on investment "tilt" and ended up being the patsy at the poker table. I should have taken my own advice when I said that "it takes 20 years to build a reputation and five minutes to ruin it. If you think about that, you'll do things differently." -- Warren E. Buffett is the chief executive of Berkshire Hathaway, a diversified holding company. -- Douglas A. Kass is President of Seabreeze Partners Management, Inc. the General Partner of Seabreeze Partners Short LP and Seabreeze Partners Long/Short LP.Doug Kass writes daily for RealMoney Silver , a premium bundle service from TheStreet.com. For a free trial to RealMoney Silver and exclusive access to Mr. Kass's daily trading diary, please click here.Know What You Own: Other financial sector stocks in the Berkshire Hathaway portfolio include M&T Bank (MTB), Torchmark (TMK) and SunTrust Banks (STI). For more on the value of knowing what you own, visit TheStreet.com's Investing A-to-Z section.How you can survive -- and even prosper -- in a rocky midyear market? Get the "best ideas to make real money" from Jim Cramer, Doug Kass, Helene Meisler and other RealMoney experts at our May 2 Investment Conference. Learn more here.