Isaac Asimov Quotes

One had to be a Newton to notice that the moon is falling, when everyone sees that it doesn't fall.

If the moon and earth were not retained in their orbits by their animal force or some other equivalent, the earth would mount to the moon by a fifty-fourth part of their distance, and the moon fall towards the earth through the other fifty-three parts, and they would there meet, assuming, however, that the substance of both is of the same density.

I was sitting in a chair in the patent office at Bern when all of a sudden a thought occurred to me: "If a person falls freely he will not feel his own weight." I was startled. This simple thought made a deep impression on me. It impelled me toward a theory of gravitation.

And the earth self-balanced on her centre hung.

I suppose I'll have to add the force of gravity to my list of enemies.

The moon is not kept in her orbit round the earth, nor the earth in her orbit round the sun, by a force that varies merely in the inverse ratio of the squares of the distances.

When Newton saw an apple fall, he found In that slight startle from his contemplation- 'Tis said (for I'll not answer above ground For any sage's creed or calculation)- A mode of proving that the earth turn'd round In a most natural whirl, called 'gravitation'; And this is the sole mortal who could grapple, Since Adam, with a fall, or with an apple.

And I was crying for gravity. It had sent me down the stairs, and I'd thought that meant something, but maybe it was just the direction that all things tend to flow.

To the Master's honor all must turn, each in its track, without a sound, forever tracing Newton's ground.

I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity.

You know how you put peanut butter on a piece of bread and the bread falls - it never falls on the bread side down, it always falls peanut butter side down. That's because of gravity.

I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.

It's physics. Pure physics, I'm falling fast and faster still. So fall with me. Fall down with me. And stay.

Falling is one of the ways of moving.

Thus far I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity. Indeed, this force arises from some cause that penetrates as far as the centers of the sun and planets without any diminution of its power to act, and that acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter, and whose action is extended everywhere to immense distances, always decreasing as the squares of the distances.

Galileo had already made a significant beginning toward a knowledge of the law of motion. He discovered the law of inertia and the law of bodies falling freely in the gravitational field of the earth.

As to your Newton, I confess I do not understand his void and his gravity; I admit he has demonstrated the movement of the heavenly bodies with more exactitude than his forerunners; but you will admit it is an absurdity to to maintain the existence of Nothing.

We see only the simple motion of descent, since that other circular one common to the Earth, the tower, and ourselves remains imperceptible. There remains perceptible to us only that of the stone, which is not shared by us; and, because of this, sense shows it as by a straight line, always parallel to the tower, which is built upright and perpendicular upon the terrestrial surface.

When the forces that hold it together go away, the body must fall.

Every particle of matter is attracted by or gravitates to every other particle of matter with a force inversely proportional to the squares of their distances.

People know a planet when they see one, and I think that's a pretty darn good test, in fact, for planethood.

Of course Pluto is a planet: It's massive enough to have its shape controlled by gravity rather than material strength, which is the hallmark of planethood.

That body is heavier than another which, in an equal bulk, moves downward quicker.

So, I'm not the only one who believes that there is such a thing as "the law of gravity," and if it's a law, it can be violated. If you hit the ground at 120 mph from 1,000 feet, you will suffer the consequences of violating what physics.about.com calls the law of gravity.