Value investing was founded on business and economic principles—but it’s really about human nature too. Over time, some of the methods for applying the value approach have evolved. For example, there is greater access to information today vs. decades ago. But human nature hasn’t changed much. Investors still get greedy—and fearful. And value investors understand that—and can apply it with the principles of business assessment and price comparison to find attractive opportunities. 

Source: Brandes on Value: The Independent Investor (1st ed.), Charles H. Brandes (McGraw-Hill, 2014)