“When we fail, we haven't tried hard enough. When we have succeed, there is no time to stop and rest.”

“Because we humans are big and clever enough to produce and utilize antibiotics and disinfectants, it is easy to convince ourselves that we have banished bacteria to the fringes of existence. Don't you believe it. Bacteria may not build cities or have interesting social lives, but they will be here when the Sun explodes. This is their planet, and we are on it only because they allow us to be.”

“We are so used to the notion of our own inevitability as life’s dominant species that it is hard to grasp that we are here only because of timely extraterrestrial bangs and other random flukes. The one thing we have in common with all other living things is that for nearly four billion years our ancestors have managed to slip through a series of closing doors every time we needed them to.”

“All men will die. All men will be called upon to pass through the veil. But only a few, only a few special men, only those who have been worthy to answer a calling from God, are given the honor to die for a cause.And in this life, in these times, all of us will be called on to make a sacrifice. When, or in what manner that sacrifice may be required, only God knows. All we can do is wait and prepare and pray that when our time comes, we will be ready to complete the task that he gives, so that when it is over, when we have done all we could, we might look to the Lord and say the same words he said : 'I have fought my way through, I have finished the work Thou didst give me to do.”

“My father once told me that a happy ending is just the place where you choose to stop telling the story. So this is where I choose to stop. More things are still going to happen, of course, some good, some bad. Some things never get any better. When people die they stay dead. None of us knows why we love, or why we stop loving, or why everyone we love we lose.”

“In essence what relativity says is that space and time are not absolute but relative both to the observer and the thing being observed, and the faster one moves the more pronounced these effects will become. We can never accelerate ourselves to the speed of light, and the harder we try(the faster we go) the more distorted we become, relative to an outside observer.”

“It's funny. When we were alive we spent much of our time staring up at the cosmos and wondering what was out there. We were obsessed with the moon and whether we could one day visit it. The day we finally walked on it was celebrated worldwide as perhaps man's greatest achievement. But it was while we were there, gathering rocks from the moon's desolate landscape, that we looked up and caught a glimpse of just how incredible our own planet was. Its singular astonishing beauty. We called her Mother Earth. Because she gave birth to us, and then we sucked her dry.”