Jack,

I don't know what to tell you that would help. You are a stubborn kid; isn't that what your dad always says? I guess he is right on that point, you'll always be a bit stubborn, even though you'll always do what they say even when you don't want to. Believe it or not you'll like being a doctor; you'll never find anything else that makes you feel the way you will when you've saved someone's life. It'll be hard sometimes; you won't always be able to save everyone.

One day, actually more than one day but one day you'll have to choose between what's right and what dad wants you to do. Do the right thing, he's fallible, he's got problems and even though he'll say he blames you; he doesn't. Someone unexpected will tell you he forgave you.

Don't let Dad go to Australia, in fact, don't ever go to Australia and never fly on Oceanic. Stay away from the numbers: 4 8 15 16 23 42. I don't actually think either of us will ever believe in fate, but it doesn't hurt to be sure.

You don't need his approval or hers. In the end you have to live your life not them.

Don't marry Sarah; she deserves to have someone who really loves her not someone who can't be sure he's not just obligated. Don't let her waste years of her life on you.

Don't make promises you can't keep. Don't do anything out of pure guilt, stay committed but don't let commitment cloud your judgment. Don't talk down to people, even if they seem to not know what their doing.

If you're ever in a plane crash, look out for polar bears. Warn Locke about the dangers of a plane hanging from a tree, he's crazy enough he'll believe you and then maybe Boone won't die. Search the island for other survivors, but be careful.

Talk to your father, he'll be gone one day and you won't know how to feel. So talk, don't yell, listen but don't take his word as law. You have your own mind. Use it. Never let him make you feel like you aren't worth it; one day you'll believe him.

If you ever meet someone named Kate Austen, you're in for a ride. Don't let her run away, but sinking is ok.

I still say don't ever go to Australia, but if Locke's right all roads end there anyway, so take medical supplies, batteries, a radio, anything you could use if you get stranded. You're life might be like a rabbit hole; don't resent it, just deal with things as they come and never write anyone off too soon. They might surprise you.

Dr. Jack Shephard