Investing is choosing how to put your money to work just like how you choose what vendor to give your business.
Here's a though experiment. If you could invest today in a company that will result in the destruction of your town (say a mining company) but you got 1% higher return compared to others, you're saying that's a perfect investment and would do it right away?
And if the answer is yes to the above, you can make that a lot darker if you want. See how far your belief goes.