Sometimes, when life gets hard and the lights go out and all hope seems to fade away, you need some perspective. And who better to get that perspective from than a 2,100-year-old Time Lord?

That's right.

Here are 12 Doctor Who quotes to get you by in life.

1. On living life

"Some live more in 20 years than others do in 80. It's not the time that matters, it's the person." - 11th Doctor

When it comes to living your life, it is all a matter of seizing the day and living each day with as much drive and as much passion as if the thing you are doing right now is the last thing you will ever do. Take the chance. Make the change. Do the thing that makes your heart race. And, when after a while you aren't scared by those things anymore, find something else that challenges you. And never stop moving.

2. On optimism at all times

"I am and always will be the optimist. The hoper of far-flung hopes and the dreamer of improbable dreams." - 11th Doctor

Sometimes, when the worst days happen, life can seem like it will never get better. But it always will, without fail. So it is your job to look with all your might and find the good things that are happening and cling to those with all you have. Because there is always good. And the world is always beautiful.

3. On miracles

"The universe is big. It's vast and complicated and ridiculous. And sometimes, very rarely, impossible things happen and we call them miracles." - 11th Doctor

Nothing is impossible, especially in a world this big and vast and beautiful. So keep your eyes open for the magic and you will find it. Every day is a new one.

4. On change

"We all change, when you think about it, we're all different people all throughout our lives, and that's okay. That's good. You've got to keep moving, so long as you remember all the people that you used to be." - 11th Doctor

No one likes change, but it is so, so necessary. I mean, take a look back at your seventh grade self and tell me if you still want to be that little twerp. Nope. But, like the Doctor said, we can never forget who we used to be, because those people made us into the person we are now. And the person we are now is shaping the person we will become. And isn't that beautiful?

5. On growing up

"When you're a kid, they tell you it's all...grow up, get a job, get married, get a house, have a kid, and that's it. But the truth is, the world is so much stranger than that. It's so much darker. And so much madder. And so much better." - Elton Pope

Okay, this one really hits home for me. My head is filled with so many dreams and wonderful aspirations that I could fill a balloon with all the hot air I produce. But you know what? Who says I can't have some of those crazy things I want? Like my grandpa said: "Not all of your dreams will come true, but some of them will so keep on going." And, if you really want something, try again. And make life as mad and unexpected and unorthodox as you can.

6. On the ups and downs

"The way I see it, every life is a pile of good things and bad things. The good things don’t always soften the bad things, but vice versa, the bad things don’t always spoil the good things and make them unimportant." - 11th Doctor

Let's face it, life is just awful sometimes. And just when you think it can't get worse, the universe cooks up something real nice for you and you get burnt. But the bad things of your life are not the full scope and sum of your existence. So ride out the bumps and pretend you are having fun until you actually are. And always look for the good things.

7. On priorities

"Never ignore coincidence. Unless, of course, you’re busy. In which case, always ignore coincidence." - 11th Doctor

Hey, sometimes your life is just too dang busy for all the things you need to do or need to see. So don't get all preoccupied with all the things you could ever think or all the things you could ever worry about. Just keep on living.

8. On our last days

"We're all stories in the end. Just make it a good one, eh?" - 11th Doctor

In the end, life is what you make it. Amid all the good things and the bad things and the crazy things, it is up to you to make it great or not. Do you want to make your life meaningful? Put meaning in it. Make good friendships, love your family, get a puppy, donate to charity, go to church. But whatever you do, know that it is up to you to determine it's quality. In the end, we will only be the sum total of the memories people have of us. So what will they remember of you?

9. On staying strong

"You don’t just give up. You don’t just let things happen. You make a stand! You say no! You have the guts to do what’s right, even when everyone else just runs away." - Rose Tyler

God gave you a gut and a conscience for a reason, and it is your job to follow that. In the face of a world spilling over with injustices, take a stand. And when people get upset at you, keep going. And when you feel like giving up, keep going. And when you have won the fight, celebrate, then find another cause to defend and another person to love. But never, ever stop fighting.

10. On exploration

"This is one corner… of one country, in one continent, on one planet that’s a corner of a galaxy that’s a corner of a universe that is forever growing and shrinking and creating and destroying and never remaining the same for a single millisecond. And there is so much, so much to see."

Life gets boring, life becomes a habit and when that happens it can be hard to see the vastness of the world in which we live. It can be hard to see beyond our own town and our own families and our own crap daily commute. But beyond that, there is a whole world of people and places that will touch your soul and refresh you heart ever time you go to them. So reach out. Make yourself uncomfortable. And see whatever you can as many times as you can and see what there is to see. And you will never be bored again.

11. On the "plan"

"Do what I do. Hold tight and pretend it’s a plan!" - 11th Doctor

Even for the most controlling of Type A people, life can get out of hand. Actually, life will always get out of hand. Because life is so much bigger than anything we could ever hold! So let go as best you can and go along for the ride. Save yourself the stress. Just go with it and pretend it's a plan!

12. On simply living

"Being alive right now is all that counts." 11th Doctor

No matter what, you are breathing. And, by definition, that means you are alive. So act like it! You are still here and you are still breathing and your (one) heart is still beating. You still have a chance and you still have a reason to fight. So let the past be your past, let your future be a surprise and let your present be your purpose.