These are some of my favorite quotes. They're grouped by subject, then author.

In our dreams we are able to fly...and that is a remembering of how we were meant to be.
-Madeline L'Engle
If you are in trouble anywhere in the world, an airplane can fly over and drop flowers, but a helicopter can land and save your life.
-Igor Sikorsky
I'll run my hand gently over the wing of a small airplane and say to him, this plane can teach you more things and give you more gifts than I ever could. It won't get you a better job, a faster car, or a bigger house. But if you treat it with some respect and keep your eyes open, it may remind you of some things you used to know - that life is in the moment, joy matters more than money, the world is a beautiful place, and that dreams really, truly are possible. And then, because airplanes speak in a language beyond words, I'll take him up in the evening summer sky and let the airplane show him what I mean.
-Lane Wallace
More than anything else, the sensation [of flying] is one of perfect peace mingled with an excitement that strains every nerve to the utmost - if you can conceive of such a combination.
-Wilbur Wright
In commemoration of the conquest of the air
By the brothers Wilbur and Orville Wright
Conceived by genius
Achieved by dauntless resolution and unconquerable faith
-Wright Brothers Memorial, Kitty Hawk, NC
All my life through, the new sights of Nature made me rejoice like a child.
-Marie Curie
Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.
-Marie Curie
"We can't go back. We don't understand everything yet."
"'Everything' is a little ambitious. We barely understand anything."
"Yeah. but that's what the first part of understanding everything looks like."
-Randall Munroe, xkcd, "Time"
"We can't answer every question."
"No. But I think we can answer any question."
-Randall Munroe, xkcd, "Time"
The cure for boredom is curiosity. There is no cure for curiosity.
-Dorothy Parker
Big whorls have little whorls
Which feed on their velocity
And little whorls have lessor whirls,
And so on to viscosity.
-Lewis F. Richardson
We make our world significant by the courage of our questions, and the depth of our answers.
-Carl Sagan, Cosmos
It is not really necessary to look too far into the future; we see enough already to be certain it will be magnificent. Only let us hurry and open the roads.
-Wilbur Wright
When I despair, I remember that all through history the way of truth and love has always won. There have been tyrants, and murderers, and for a time they can seem invincible, but in the end they always fall. Think of it... always.
Fourscore and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation or any nation so conceived and so dedicated can long endure. We are met on a great battlefield of that war. We have come to dedicate a portion of that field as a final resting-place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But in a larger sense, we cannot dedicate, we cannot consecrate, we cannot hallow this ground. The brave men, living and dead who struggled here have consecrated it far above our poor power to add or detract. The world will little note nor long remember what we say here, but it can never forget what they did here. It is for us the living rather to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us--that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion--that we here highly resolve that these dead shall not have died in vain, that this nation under God shall have a new birth of freedom, and that government of the people, by the people, for the people shall not perish from the earth.
-Abraham Lincoln, The Gettysburg Address
I learned this at least by my experiment: that if one advances confidently in the direction of his dreams, and endeavors to live the life which he has imagined, he will meet with a success unexpected in common hours.
-Henry David Thoreau, Walden