In this edition of The Motley Fool's "Ask a Fool" series, Motley Fool One analyst Jason Moser takes a question from a reader who asks: "Will markets go up forever?" While one can assume yes (at least for the purposes of our lifetimes), looking further out can certainly raise a host of questions.

As emerging markets continue to, well, emerge, and technology continues to improve, more people will need more things, and more things will become more accessible to more people. And as the world's population grows, it certainly makes sense that markets will grow with it. But it won't be a straight line upward, and at the end of the day, it behooves the individual investor to recognize that anything is possible and remain properly diversified.