In the following video, Fool contributor Matt Thalman discusses a topic affecting all investors: deciding which companies meet our personal moral guidelines.

Matt says that while many companies and industries may appear morally upstanding on the surface, things can change when they're viewed from a different perspective. For example, some consumers may be outraged by how much money they pay to utility companies every month, but the moral dilemmas can go much deeper when looking at things like the environmental damage caused by coal-fired power plants, or the threat posed by nuclear reactor malfunctions and the disposal of spent fuel rods.

As investors, Matt says, we all need to decide what we consider moral or immoral and then decide which companies to support accordingly.

Fool contributor Matt Thalman owns shares of Apple. Check back Monday through Friday as Matt explains what caused the Dow's winners and losers of the day, and every Saturday for a weekly recap. Follow Matt on Twitter: @mthalman5513

The Motley Fool recommends Apple, Coca-Cola, and Nike and owns shares of Apple and Nike. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.