"Innovations in science and technology are the engines of the 21st-century economy; if you care about the wealth and health of your nation tomorrow, then you'd better rethink how you allocate taxes to fund science. The federal budget needs to recognize this."

"If the universe is anything, it should be fun."

"If God is the mystery of the universe, these mysteries, we're tackling these mysteries one by one. If you're going to stay religious at the end of the conversation, God has to mean more to you than just where science has yet to tread."

"The urge to want some bit of information to be true often clouds our ability to assess why that information may be false."

"I know that the molecules in my body are traceable to phenomena in the cosmos. That makes me want to grab people on the street and say: 'Have you HEARD THIS?"

"Robots are important also. If I don my pure-scientist hat, I would say just send robots; I'll stay down here and get the data. But nobody's ever given a parade for a robot. Nobody's ever named a high school after a robot. So when I don my public-educator hat, I have to recognize the elements of exploration that excite people. It's not only the discoveries and the beautiful photos that come down from the heavens; it's the vicarious participation in discovery itself."

"Dinosaurs are extinct today because they lacked opposable thumbs and the brainpower to build a space program."

"The universe is almost 14 billion years old, and, wow! Life had no problem starting here on Earth! I think it would be inexcusably egocentric of us to suggest that we're alone in the universe."

"And I submit to you, that science, scientific discovery, especially cosmic discovery, does not become mainstream until the artist embraces the fruits of those discoveries."

"Philosophically, the universe has really never made things in ones. The Earth is special and everything else is different? No, we've got seven other planets. The sun? No, the sun is one of those dots in the night sky. The Milky Way? No, it's one of a hundred billion galaxies. And the universe - maybe it's countless other universes."

"I'm perennially intrigued how people who lead largely evidence-based lives can, in a belief-based part of their mind, be certain that an invisible, divine entity created an entire universe just for us, or that the government is stockpiling space aliens in a secret desert location."

"When we see animals doing remarkable things, how do we know if we're simply seeing tricks or signs of real intelligence? Are talented animals just obeying commands, or do they have some kind of deeper understanding? One of the biggest challenges for animal researchers is to come up with tests that can distinguish between the two."

"The problem, often not discovered until late in life, is that when you look for things in life like love, meaning, motivation, it implies they are sitting behind a tree or under a rock. The most successful people in life recognize, that in life they create their own love, they manufacture their own meaning, they generate their own motivation. For me, I am driven by two main philosophies, know more today about the world than I knew yesterday. And lessen the suffering of others. You'd be surprised how far that gets you."

"You know that passage in the Bible that says, "And the meek shall inherit the Earth? Always wondered if that was mistranslated. Perhaps it actually says, "And the geek shall inherit the Earth."

"When students cheat on exams it's because our school system values grades more than students value learning."

"There are thousands of asteroids whose orbit in the Solar System crosses that of Earth. And we have a little acronym for them - NEOs: near Earth objects. And our biggest goal is to try to catalogue them, so we know in advance if one is going to put us at risk."

"Science is basically an inoculation against charlatans."

"When you organize extraordinary missions, you attract people of extraordinary talent who might not have been inspired by or attracted to the goal of saving the world from cancer or hunger or pestilence."

"The less evidence we have for what we believe is certain, the more violently we defend beliefs against those who don't agree."

"I have a personal philosophy in life: If somebody else can do something that I'm doing, they should do it. And what I want to do is find things that would represent a unique contribution to the world - the contribution that only I, and my portfolio of talents, can make happen. Those are my priorities in life."

"God is an ever-receding pocket of scientific ignorance."

"There is no shame in not knowing. The problem arises when irrational thought and attendant behavior fill the vacuum left by ignorance."

"If you're going to lead a space frontier, it has to be government; it'll never be private enterprise. Because the space frontier is dangerous, and it's expensive, and it has unquantified risks. And under those conditions, you cannot establish a capital-market evaluation of that enterprise. You can't get investors."

"To make any future that we dreamt up real requires creative scientists, engineers, and technologists to make it happen. If people are not within your midst who dream about tomorrow - with the capacity to bring tomorrow into the present - then the country might as well just recede back into the cave because that's where we're headed."

"In the beginning, there was physics. "Physics" describes how matter, energy, space, and time behave and interact with one another. The interplay of these characters in our cosmic drama underlies all biological and chemical phenomena. Hence everything fundamental and familiar to us earthlings begins with, and rests upon, the laws of physics. When we apply these laws to astronomical settings, we deal with physics writ large, which we call astrophysics."

"All the traditional STEM fields, the science, technology, engineering, and math fields, are stoked when you dream big in an agency such as NASA."

"We explore our environment, more than we are compelled to utter poetry, when we're toddlers. We start doing that later. Before that happens, every child is a scientist."

"What people are really after is, what is my stance on religion or spirituality or God? And I would say, if I find a word that came closest, it would be agnostic."

"The good thing about science is that it's true whether or not you believe in it."

"People cited violation of the First Amendment when a New Jersey schoolteacher asserted that evolution and the Big Bang are not scientific and that Noah's ark carried dinosaurs. This case is not about the need to separate church and state; it's about the need to separate ignorant, scientifically illiterate people from the ranks of teachers."

"Informed ignorance provides the natural state of mind for research scientists at the ever-shifting frontiers of knowledge. People who believe themselves ignorant of nothing have neither looked for, nor stumbled upon, the boundary between what is known and unknown in the cosmos."

"The Universe is under no obligation to make sense to you."

"In the animal kingdom, one of the keys to survival is to outwit your enemies. And when you're surrounded by carnivores, one of the best strategies is to fade into the background and disappear."

"I think that intelligence is such a narrow branch of the tree of life - this branch of primates we call humans. No other animal, by our definition, can be considered intelligent. So intelligence can't be all that important for survival, because there are so many animals that don't have what we call intelligence, and they're surviving just fine."

"I think the greatest of people in society carved niches that represented the unique expression of their combinations of talents, and if everyone had the luxury of expressing the unique combinations of talents in this world, our society would be transformed overnight."

"We live in the kind of society where, in almost all cases, hard work is rewarded."

"These philosophically fun ideas usually satisfy nobody. Nonetheless, they remind us that ignorance is the natural state of mind for a research scientist. People who believe they are ignorant of nothing have neither looked for, nor stumbled upon, the boundary between what is known and unknown in the universe."

"There is no science in this world like physics. Nothing comes close to the precision with which physics enables you to understand the world around you. It's the laws of physics that allow us to say exactly what time the sun is going to rise. What time the eclipse is going to begin. What time the eclipse is going to end."

"Where ignorance lurks, so too do the frontiers of discovery and imagination."

"During our brief stay on planet Earth, we owe ourselves and our descendants the opportunity to explore - in part because it's fun to do. But there's a far nobler reason. The day our knowledge of the cosmos ceases to expand, we risk regressing to the childish view that the universe figuratively and literally revolves around us. In that bleak world, arms-bearing, resource-hungry people and nations would be prone to act on their 'low contracted prejudices.' And that would be the last gasp of human enlightenment - until the rise of a visionary new culture that could once again embrace, rather than fear, the cosmic perspective."

"In some ways, we are traveling in time now. We just happened to be prisoners of the present in the eternal transition from the past to the future."

"Humans aren't as good as we should be in our capacity to empathize with feelings and thoughts of others, be they humans or other animals on Earth. So maybe part of our formal education should be training in empathy. Imagine how different the world would be if, in fact, that were 'reading, writing, arithmetic, empathy.'"

"I know of no time in human history where ignorance was better than knowledge."

"If the whole world shared such experiences, we would then have common dreams and everybody could begin thinking about tomorrow. And if everybody thinks about tomorrow, then someday we can visit the sky together."

"Science, enabled by engineering, empowered by NASA, tells us not only that we are in the universe but that the universe is in us. And for me, that sense of belonging elevates, not denigrates, the ego."

"We spend the first year of a child's life teaching it to walk and talk and the rest of its life to shut up and sit down. There's something wrong there."

"We are all connected; To each other, biologically. To the earth, chemically. To the rest of the universe atomically."

"A bullet fired level from a gun will hit ground at same time as a bullet dropped from the same height. Do the Physics."

"There are a lot of things you can do in space, and space essentially is unlimited resources. We are climbing over ourselves here looking for the next source of energy. The universe has an unlimited source of energy."

"I've spent quality time in the aerospace community, with my service on two presidential commissions, but at heart, I'm an academic. Being an academic means I don't wield power over person, place or thing. I don't command armies; I don't lead labor unions. All I have is the power of thought."