“If I only knew then what I know now.”

How many times have you caught yourself agonizing over some past career or financial decision? If you’re 30 or older, I’m guessing your answer falls somewhere between “ten times a day” and “once a week.”

Thanks to science, we know that the human brain doesn’t reach full maturity until around age 25. This means that most of us spend our early, mushy-brained 20s doing (or not doing) things that our fully developed 30- 40- and 50-year-old brains come to regret. We party too much, study too little, drop out of school, date the wrong people, and choose the wrong career path. We wreck our finances by overspending, not saving, and using (and abusing) credit.

Looking back, it’s easy to see that we could have spent those years developing new skills, exploring new career opportunities or side hustles, or saving the money our 20-something selves spent on clubs, bars, and all the other bullsh*t. We look back on those years – years that, for many of us, were free of additional responsibilities like taking care of kids and/or aging parents – and we say:

“If only I’d known then what I know now…”

You can’t change the past. Hell, 20-year-old clubbing, partying you probably wouldn’t have listened to responsible, grown-up 30-year-old you, anyway. But here’s the thing: Even if you have some regrets, all is not lost.

I find inspiration in this Chinese proverb:

“The best time to plant a tree was 20 years ago.
The second best time is now.”

The key word in that proverb is now.

If you’re not happy with the state of your finances (income, earning potential, net worth, etc.) or career path, it’s time to focus on the now. You didn’t know then, but you do know now — so why not do something about it? Yes, you may have wasted part of your 20s. But so what? So you made a few terrible decisions. You f*cked up once or twice. Why let those decisions – decisions that you made, literally, before your brain was fully functioning – affect the rest of your life?

Your life is the result of decisions you made in the decade prior. If you’re 40 or 50 years old, your life and everything in it is the result of decisions you made in your 30s or 40s, respectively. This means whatever choices you are making today will determine the state of your life in your 50s or 60s.

Sure, the best time to pursue a degree, learn a skill, or start a retirement fund might have been 20 years ago. But like the proverb says, the second-best time to do those things is right now. The version of you that’s reading this – the you with the fully developed brain and two or three additional decades of life experience – has the power to start making different choices.

Because you do know now. And now is the time to prove it to yourself.  As long as you have breath in your lungs, it’s never too late.