Benjamin Graham had many investment principles, and this is yet another collection of his great ideas taken from his famous book "The Intelligent Investor." This strategy selects companies with a low debt load, has the ability to pay off the debt it does have, and has a long track record of healthy earnings. Graham was a big fan of using not just the P/E ratio, but also the price-to-book ratio to pick stocks whose fundamentals indicated they were currently undervalued by price. Finally, Graham suggested investing in stocks that paid dividends.