Work harder. Be less socially shy.
Don’t fall into debt. Save some money.
Even if I limit “wisdom” only to “the ability to keep my temper” – something I lacked in youth and have attained in later age – then, yes! That one change alone would have led to a much happier life. If you allow me to keep other aspects of my life-long acquired wisdom – patience, tolerance, moderation, inquiry, skepticism, respect, etc. – then hell yes!
I’d definitely start being more health conscious at a younger age. No way I would have ever started smoking. I quit, and that was a really positive experience, but I’d trade it for not having started.
It’s almost depressing to think how much I could have achieved with only a fraction of the insight I have now into how things, and more particularly I, work.
I read a fascinating book about this: Replay. It’s an account of an over-40 schlub who dies of a heart attack and re-awakens as a teenager again, but all his memories are intact.
Assuming that scenario for me; I’m pretty much where I want to be, but I’d try for an easier path.
Think of it this way: I played a season of little-league ball when I was 11. I wasn’t great, wasn’t lousy, just kinda average for an 11 year old.
Now imagine that a 40 year old major-leaguer at the end of his career wakes up one morning in the body of the 11 year old I used to be, with all his baseball knowledge and instincts intact. Once he got used to being in my body, he’d tear up the league. He’d know how to hit and field, from a lifetime of practice in hitting against the best pitching, and fielding the toughest hitters’ hits. Every at-bat would be an extra-base hit, even if he couldn’t find the juice in my arms to hit home runs. He’d catch every ball my young legs could get him to, and his throws wouldn’t be powerful, given my arms, but they’d be accurate.
Well, I’ve got major-league experience at life, by my standards at least.
And because of that, it’s hard to imagine the point of going back to any earlier than, say, age 17, on the cusp of adulthood. Keep a couple of important friendships intact that I screwed up in my last few months of high school, then off to college at a large university instead of the small college I actually went to, so I could jump straight into graduate classes, spend my time with other adults, and be way further along much earlier in life than I was this go-around.
I’d be bringing a lot more to the game than I did in my 40s, let alone my 20s. It would be interesting to see just what that life would be like.
But I’d want to finish living the life I’m in before jumping back in time to age 17. I’m really quite happy with the life I’ve got. I’ve got a wonderful wife, a son who I love like crazy even when he’s driving me nuts, a job that, after a difficult year or so, has become mostly fun once again, and I’m comfortably well off financially. It took me a looooooong time to finally feel like I was in the life I really wanted to be in - long enough that I know just how lucky I am - but I’ve been there for the past half-dozen years. The hell if I’m trading that away for anything. I want to live the life I’ve got as fully and well as I can manage, and above all I want to be with my son every step of the way as he grows up. And I get to do that! I’m already where I want to be, and going where I want to go.
I’d have it so that I understood in my mid / late teens (a thing I totally failed to “get” in the life which I’ve actually lived, leading to several years of a miserable [for me and others] and ultimately pointless cluster-fuck of a time at university): what going to university, is primarily about – i.e. maximising the likelihood of getting to earn my living as an adult in a way that would be lucrative, and fulfilling. And that I decided on that basis, whether to go to university or take a different path.
And, would have it that I realised and accepted early on, what had in fact been pretty plain to see: that I’m a born bachelor and solitary – and that I resisted the pressures from various directions, to pair off and / or score with girls. My taking this tack would have spared several ladies a good deal of misery; and made my own life overall, less traumatic and frustrating, and given me a lot more opportunity to do more agreeable and fulfilling, for me, stuff in various of life’s many other departments.
John Betjeman (1906 – 1984), British poet / writer / broadcaster / keen exponent of all things nostalgic (and seemingly not a notable libertine, and a faithful husband though many years of marriage) is reported to have expressed, near the end of his life, very similar sentiments.
Well this isn’t very encouraging. Does this mean I’m near the end of my life?
Oh, gosh, I didn’t mean it that way 
smack: – it just came into my head, I think, in that in saying such a thing at all, Betjeman was perhaps being unusually frank for a man of his time.
I would have remained in Architecture school, rather than switching majors 5 times. Of course, that would have totally changed the trajectory of my life, and I probably never would have met my partner a couple of decades later.
And I would have gotten a handle on my diabetes much sooner.
I would have gotten a job in high school, part time lifting boxes at some stationery store or something. Earn a little money, get some job experience, and start dating. Different major in college, studying lighting or set design. I wouldn’t necessarily be in any better place or better financial situation, but I would have spent more time doing something that I loved rather than just working to earn money.
I would have stopped watching TV much earlier than I did.
You didn’t have a coach drumming the “value of cardio” into your head?
I hesitate to believe there are words describing how much better my life would be if this were possible
Although I nominate starting me in like…4th grade instead of all over.
Being a baby would be boring as hell
Yeah, if I could hit reset at 12, when my maternal grandfather died, things certainly would’ve been different, if not better. Lessee…
*Skipped out on the religious fundamentalism my mother turned to in fear for her / our mortality. It kicked off a life-long terror of the “afterlife.”
*Lost my virginity earlier instead of waiting for The One. Maybe then there wouldn’t have been so many hangups to overcome.
*Gone to college right out of high school. That decision definitely would’ve begun establishing the boundaries that I needed with my mother, that are still difficult to uphold to this day and I’m now 47.
*Married for much different reasons. I love my husband, but many long years of caregiving a non-compliant person has worn on me. And now that he’s terminal, most of the last decade has been nothing but a waste of opportunities and nothing but stress, pain and heartbreak.
*Got better help for my mental illness sooner. Since I pretty much went it alone for the longest, I feel like if I had better information, support and assistance, things wouldn’t have gotten nearly as bad for quite so long.
*Finally, I’d have stayed on top of my health much more strenuously instead of using food for comfort. I wish I’d have found my solace in endorphins from exercise and healthy living, then trying to keep diabetes at bay, re-training myself in the proper way to eat and dealing with a middle-aged body seriously in need of more TLC before there’s real problems.
So, I’m not sure where that’d put me overall, because I’m sure even that trajectory would come with its own set of challenges and issues. But I think I’d feel a little less adrift and more like I’m living the life I was meant to. Instead of just trying to constantly keep my head treading above water.
Depends on how you define drumming. Telling us that we need to be in good shape? Sure. But that led me to run 9 miles a week. I didn’t get over 20 miles a week until I was a senior in college. There is a huge difference between being able to run 3 miles and being able to run for 2 hours.
(I didn’t read any other replies, so this is my opinion uninfluenced by other poster’s insights.)
I’ve been lucky, and grew up in a relatively drama free childhood. (No disabilities, not utter poverty, no war, no gang violence, no domestic abuse.)
Anything that’s held back my “success” (either in relationships or career arenas) has been from within myself, via low self esteem and/or laziness. (To be brutally honest. 
) I’m 50 now, and I haven’t found the quick and easy answers to those issues.
Bottom line: I think 90% of my early life would have been pretty much the same, although I might have sucked it up stayed in the USN for 20 instead of 6 years. (Getting a job as a “tech rep” was harder than I thought it would be! I worked minimum wage for five years before I landed one through sheer luck.)
There’s certainly some fuzziness. But the way I’m thinking of it, you have the general rules of life in hand, but you don’t know anything about specific incidents or events. So, for example, you might have a better idea how to deal with a controntation situation, but not know how any specific confrontation would turn out if you did X versus Y. You might appreciate the value of integral calculus more (or less) but you wouldn’t actually know it.
Wisdom is knowledge, born of experience (including learning) during your life. Emotional maturity is about feeling.