I’m 37, make $52,000 a year and have just begun putting money into a 401(k). With thirty years until retirement, I’m inclined to believe that a somewhat aggressive investing strategy will pay off in the long run. But given the immediate uncertainty in the economy and the market, am I better off investing in less risky funds in the short term? — Erik, Brooklyn, N.Y. If you’re waiting for uncertainty, immediate or otherwise, to die down before you embark on your long-term investing strategy, you’re going to have a long wait. Things are never certain in the economy and the market. Whether it’s concerns about the ability of a new Congress and a second Obama administration to get a handle on our massive budget deficit, worries about the effect Superstorm Sandy might have on future job growth, trepidation over the approaching fiscal cliff or anxiety stemming from the European debt crisis, uncertainty is a constant. Or, to borrow a phrase from Gilda Radner’s classic Roseanne Roseannadanna character from the early days of Saturday Night Live: “It’s always something — if it ain’t one thing, it’s another.” So the more important question you should be asking yourself is this: What kind of investor do you want to be, given that you’ll always have to deal with uncertainty? As I see it, you have two choices: you can be a reactive investor or a systematic investor. Reactive investors spend most of their time figuring how to rejigger their investments to take advantage of new developments on the investing scene or to prevent those developments from hurting them. Related: Worried about the Fiscal Cliff: Should I Sell? If they see that inflation is ticking up or interest rates are starting to climb, they may shift money out of bonds and into gold or commodities. If they believe economic growth is weakening and the economy may be slipping into recession, they might get into defensive stocks or buy long-term bonds. If you like making lots of moves with your investments, this is the right camp for you — for the reactive investor, investing is a never-ending guessing game. There will always be something going on in the economy or the markets that will catch your attention and require action. The downside is that it’s tough — I would say virtually impossible — to make the right call consistently. Very often what seems like the obvious isn’t. Back in early 2009, for example, the last place most investors wanted to be was in stocks, which had just plummeted nearly 60% from their 2007 high. Moving to bonds or cash seemed a more prudent bet. Of course, we now know that since that low, stock prices have climbed more than 100%, while bonds gained about 28% and cash returned less than 1%. A systematic investor, by contrast, starts with the premise that you can’t outguess the markets. The best you can do is set a strategy that will allow you to participate in the long-term upswing of stock prices, while hedging against the inevitable downturns by also holding some bonds and cash. This type of investor doesn’t feel compelled to act every time a new piece of economic data flickers across his computer screen or a headline warns of impending doom. Related: Retirement Savings: Quick Guide to How Much You’ll Need Rather, the systematic investor realizes that one decision is key: determining the mix of stocks, bonds and cash that will give him a shot at reasonable returns while holding the risk of short-term setbacks to an acceptable level. Once he sets that mix, the systematic investor pretty much leaves it alone, except to rebalance periodically to bring the mix back to its original proportions. If you prefer to be a reactive investor, I can’t offer you much advice. I don’t believe investors can consistently make the right moves in order to take advantage of market fluctuations. I think they’re more likely to end up hurting themselves. No worries, though. There are plenty of brokers and other advisers out there all too willing to cater to the reactive investor’s need to act. In fact, the standard pitch from most of Wall Street and much of the financial services industry is that they know what moves to make, and for a price they’re willing to help you make the unending series of decisions you’ll face as a reactive investor. If you want to join the systematic camp, however, then I suggest you stop obsessing about uncertainty and instead focus on creating a portfolio that makes sense for the long haul, in your case for someone with thirty or so years until retirement. Related: Why There’s No Such Thing as Risk-Free Investing Typically, retirement investors with that sort of time horizon invest between 70% and 90% of their savings in stocks with the rest in bonds, although the blend you choose should reflect how much you’re willing to see your account balance dip during market downturns. (To get a feel for the tradeoff between risk and return for different stocks-bonds mixes, you can check out Morningstar’s Asset Allocator tool.) Of course, just because you arrive at the right mix doesn’t mean uncertainty will go away. It will always be there. But if you take the systematic approach, then at least you won’t have to react to it day after day after day.