<prompt> Human: I could used a little explanation, because I think Im misunderstanding something about investments. Basically, beyond taking my company match, Im wondering if its wise to invest or just pay off my mortgage. My inclination is pay off the mortgage. My reasoning works like this:The mortgage is a guaranteed 4-5 return just on not paying interest. In the event of a job loss or recession, I still have the house and will still need it.While I understand investments can return more per year, theres no guarantee that there will be money there when I need it. My grandfather was an engineer and economics professor and invested all his life. He still died nearly broke because he lost most of his wealth in the recession. He sold a house and invested the money, but the house ended up being worth millions by the time his money was worth nothing.With increasing globalization its likely the US dollar will be further reduced in value over the next 30 years Im not predicting any kind of collapseapocalypserevolution, just long term devaluation, but population will continue to increase and people will need homes, so home prices would be unlikely to collapse as quickly Im in a major metro area.What am I missing? Please, change my mind.  <response>: My grandfather was an engineer and economics professor and invested all his life. He still died nearly broke because he lost most of his wealth in the recession.What, specifically, was your grandfather invested in?People who held stocks through the recession without selling have done well, even including the temporary decline.People who need money in the short term should be holding more bonds than stocks. A bond-heavy portfolio would have survived the 2008 recession with flying colors.The takeaway here isnt that investing means you money can go to 0 because if you do it right, it cant, it means you need to educate yourself on how to invest properly.Read the long-term investing start-up kit link in the sidebar. 