But if travel isn't desired or tenable, what about voyaging within? In a sense, virtually every new thought and idea you have can help you feel younger. So your ingrained assumptions and beliefs may now merit some "re-visioning." And if your internal journey enables you to see things afresh, you'll thereby recapture some of the original surprise and wonder of your inner child. Re-assess the things you've long taken on faith and you just might retrieve some particle of that time when you were beginning to grasp what before had been inconceivable to you. And linked to all of this:

(10) Become a Lifelong Learner. The idea of introducing yourself to unfamiliar subjects of study—whether it's learning a foreign language that's always interested you; going to galleries and museums to develop your appreciation of the fine arts; reading about American, European, or Asian history; taking an online course in mathematics, physics, or cosmology; exploring the ideas of the world's great philosophers; or, for that matter, taking up the guitar (or cigar box banjo!)—regularly learning new things assists you in perpetuating feelings of youth. As Gandhi famously put it: "Live as if you were to die tomorrow, and learn as if you were to live forever." Staying inquisitive about things and enthusiastically increasing your knowledge of them enables you to stay young in mind.

Needless to say, the practice of continually educating yourself also energizes you mentally. So stay open to new information, even if it's not immediately applicable to anything—like a child who, not-very-discriminately, absorbs (almost by osmosis) many new things daily. Don't let your brain atrophy from lack of use. If, finally, experiencing yourself as old has at least as much to do with mental than physical decline, endeavor to constantly nourish your mind with fresh material to digest

And this new learning hardly need focus on the academic. You can give full rein to your imagination as well—one of the things that children typically are better at than adults. Catch up with them by creatively reflecting on all the new learning you expose yourself to. Which will keep your wits as sharp as they were when—again, as a child—fascinated, or confused, by so many things, both your mind and senses were busy processing novel stimuli to better assimilate it.

(11) Be more flexible and open-minded. Despite having an optimal diet and exercise program, your body will continue to grow older. Physical aging can be slowed down (e.g., if you reduce fat intake, stop smoking, and drink only in moderation), but it can't really be halted or reversed (Peter Pan and Benjamin Button, notwithstanding).

Your intellect, however, is a different story. There are all sorts of things you can do to retain a youthful mentality. And this isn't anything medical (like taking supplements to prevent brain cell death). Rather, it's about altering attitudes, looking at things from a broadened, more humanistic perspective—at once more intricate, compassionate, understanding, and forgiving. In this sense, what keeps you young is your willingness to evolve your consciousness: to see things from a more detached vantage point that may have eluded you earlier. Whenever you're able to liberate yourself from old, out-of-date biases, you become younger at heart.

When's the last time you changed your opinion on something? Questioned your assumptions? habits? routines? Undeniably, as we age there's a tendency to become more rigid in our thinking and behavior. And this rigidity itself ages us—whereas being open to new viewpoints, and new ways of thinking about and doing things, serves to hold back the clock. The felt passing of time is largely psychological. And recent research has shown that your experience of sameness speeds up subjective time, whereas introducing more variability into your life slows it down. Staying informed of changes in technology, following national and international affairs, keeping abreast of cultural trends, are all aligned with the outlook of agelessness.

(12) Cultivate Your Creativity and Self-Expression. If you've spent most of your life thinking inside the box (and regrettably, our educational system supports this tendency), it's time to step outside it: To generate new modes of being in the world, new methods of experiencing—and interpreting—things, new ways of relating to people, new approaches for reaching goals. Recall how you "dreamed up" new games as a child. Your creativity was altogether natural—it was in you to innovate. Well, it still is, however long it's been since you last tapped into it. And right now would be a good time to reclaim this inborn imaginativeness, originality, and ingenuity.

Consider also how, historically, you may have curbed your free expression because you feared others' negative reactions to it. If over the years you've become more self-validating and less dependent on others' approval, you no longer need be so concerned about the "hazards" of being more fully yourself. And achieving eternal youth has a great deal to do with reclaiming that less inhibited, childlike part of you that once enabled you to feel buoyantly, irrepressibly alive.

 

That's about it: The right way to age . . . into agelessness. On the contrary, the wrong way has perhaps been best summed up by Daniel Prokop, who wrote (in his Leaving Neverland: Why Little Boys Shouldn't Run Big Corporations, 2011): "In a desperate attempt to stay young forever we have achieved eternal childishness, rather than eternal youth." But follow these more "adult" steps to staying young—which can actually help integrate your child and adult parts—and you'll succeed in a youthful aging that will immunize you from the unsettling experience of growing old.

Lastly, consider (cosmetically enhanced) 74-year-old Jane Fonda's advice to her readers in Prime Time (2011) on how to transform their thinking about getting older: "The old way of looking at age is an arch, you're born . . . you peak. But the new way of looking at it is [like] a staircase—you ascend. . . ."