Yep: Shark Tank star Barbara Corcoran just celebrated her 70th birthday by holding her own funeral. First, she lay in a coffin while family and friends paid their respects. Then she jumped out of the coffin and danced the tango to Diana Ross's "I'm Alive!"

As Barbara said, "What the heck. You only die once, you might as well be around for it!"

All of which might sound odd. (Mark Cuban found it "creepy" and said he didn't want to look.) But it does raise a larger point.

Barbara Corcoran will actually die someday. Someday, I will die. 

Someday, you will die.

How did reading that last sentence make you feel?

Possibly it's a depressing thought, one that makes life seem meaningless. Or maybe that thought is liberating and empowering. Maybe thoughts of your own death inspire you to make the best of every day: Not in the mindlessly pursuit of instant gratification but with the intention to live every moment as meaningfully and purposefully as possible.

Either way, you get to choose how you will respond to that sentence, because how you react to it, and to everything else that happens to you, truly is a choice.

That premise is an underlying tenet of Stoicism. Stoicism has nothing to do with being stone-faced and showing no emotion; Stoicism is a practical philosophy that says while you can never control everything that happens, you can always control how you respond.

That's especially true when you reflect upon your own mortality. 

It's easy to live mindlessly when you think you'll live forever. When you not only face but actually embrace the fact your days are numbered, that should change your perspective. 

Today could be the last day you get to make a difference in another person's life. Today could be the last day you get to tell the people close to you that you love them. 

Want to start a business? Do it now. Don't wait five years; you may not have five years. Want to change careers? Wait too long and you may never get the chance. Want to learn something, accomplish something, become something? Embark on that path now.

Someday we will all die. That's a fact--but it's an easy fact to forget.

Make sure you never have to look back and wish you had lived today differently. Or any other day. Time is the most precious asset you have.

Don't waste it.