[My] numberless observations... made on the Strata... [have] made me confident of their uniformity throughout this Country & [have] led me to conclude that the same regularity... will be found to extend to every part of the Globe for Nature has done nothing by piecemeal. [T]here is no inconsistency in her productions. [T]he Horse never becomes an Ass nor the Crab an Apple by any intermixture or artificial combination whatever[. N]or will the Oak ever degenerate into an Ash or an Ash into an Elm. [H]owever varied by Soil or Climate the species will still be distinct on this ground. [T]hen I argue that what is found here may be found elsewhere[.] When proper allowances are made for such irregularities as often occur and the proper situation and natural agreement is well understood I am satisfied there will be no more difficulty in ascertaining the true quality of the Strata and the place of its possition [sic] than there is now in finding the true Class and Character of Plants by the Linean [sic] System.

[Newton is the] British physicist linked forever in the schoolboy mind with an apple that fell and bore fruit throughout physics.

[Wolfgang Bolyai] was extremely modest. No monument, said he, should stand over his grave, only an apple-tree, in memory of the three apples: the two of Eve and Paris, which made hell out of earth, and that of Newton, which elevated the earth again into the circle of the heavenly bodies.

A man would have to be an idiot to write a book of laws for an apple tree telling it to bear apples and not thorns, seeing that the apple-tree will do it naturally and far better than any laws or teaching can prescribe.

An apple falls in front of Newton, a pot boils before Papin, a flaming sheet of paper floats before the eyes of Montgolfier. At intervals a discovery bursts forth like a mine explosion in the deeps of science, and a whole ledge of prejudice crumbles, and the living rock of truth is suddenly laid bare.

And make us as Newton was, who in his garden watching
The apple falling towards England, became aware
Between himself and her of an eternal tie.

Chemistry teaches us to regard under one aspect, as various types of combustion or oxidation, the burning of a candle, the rusting of metals, the physiological process of respiration, and the explosion of gunpowder. In each process there is the one common fact that oxygen enters into new chemical combinations. Similarly to the physicist, the fall of the traditional apple of Newton, the revolution of the earth and planets round the sun, the apparitions of comets, and the ebb and flow of the tides are all phases of the universal law of gravitation. A race ignorant of the nature of combustion or of the law of gravitation, and ignorant of the need of such generalisations, could not be considered to have advanced far along the paths of scientific discovery.

Children are told that an apple fell on Isaac Newton’s head and he was led to state the law of gravity. This, of course, is pure foolishness. What Newton discovered was that any two particles in the universe attract each other with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them. This is not learned from a falling apple, but by observing quantities of data and developing a mathematical theory that can be verified by additional data. Data gathered by Galileo on falling bodies and by Johannes Kepler on motions of the planets were invaluable aids to Newton. Unfortunately, such false impressions about science are not universally outgrown like the Santa Claus myth, and some people who don’t study much science go to their graves thinking that the human race took until the mid-seventeenth century to notice that objects fall.

Did Newton, dreaming in his orchard there
Beside the dreaming Witham, see the moon
Burn like a huge gold apple in the boughs
And wonder why should moons not fall like fruit?

Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree.

Facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts do not go away while scientists debate rival theories for explaining them. Einstein's theory of gravitation replaced Newton's, but apples did not suspend themselves in mid-air pending the outcome.

For the birth of something new, there has to be a happening. Newton saw an apple fall; James Watt watched a kettle boil; Roentgen fogged some photographic plates. And these people knew enough to translate ordinary happenings into something new...

Good teachers deserve apples; great teachers deserve chocolate.
A favorite quotation, written in calligraphy on his office door.

Gravity tells us why an apple doesn’t go to heaven.

Historical theories are, after all, intellectual apple carts. They are quite likely to be upset. Nor should it be forgotten that they tend to attract, when they gain ascendancy, a fair number of apple-polishers

I am putting together a secular bible. My Genesis is when the apple falls on Newton's head.

I'm not smart. I try to observe. Millions saw the apple fall but Newton was the one who asked 'why.'

If the apple hit Newton’s nose, Newton’s nose hit the apple.

If you wish to make an apple pie from scratch, you must first invent the universe.

In a manner which matches the fortuity, if not the consequence, of Archimedes’ bath and Newton’s apple, the [3.6 million year old] fossil footprints were eventually noticed one evening in September 1976 by the paleontologist Andrew Hill, who fell while avoiding a ball of elephant dung hurled at him by the ecologist David Western.

In science “fact” can only mean “confirmed to such a degree that it would be perverse to withhold provisional assent.” I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.

In the year 1666 he retired again from Cambridge... to his mother in Lincolnshire & whilst he was musing in a garden it came into his thought that the power of gravity (wch brought an apple from the tree to the ground) was not limited to a certain distance from the earth but that this power must extend much farther than was usually thought. Why not as high as the moon said he to himself & if so that must influence her motion & perhaps retain her in her orbit, whereupon he fell a calculating what would be the effect of that supposition but being absent from books & taking the common estimate in use among Geographers & our seamen before Norwood had measured the earth, that 60 English miles were contained in one degree of latitude on the surface of the Earth his computation did not agree with his theory & inclined him then to entertain a notion that together with the force of gravity there might be a mixture of that force wch the moon would have if it was carried along in a vortex.
[The earliest account of Newton, gravity and an apple.]

It must have appeared almost as improbable to the earlier geologists, that the laws of earthquakes should one day throw light on the origin of mountains, as it must to the first astronomers, that the fall of an apple should assist in explaining the motions of the moon.

It seems as though no laws, not even fairly old ones, can safely be regarded as unassailable. The force of gravity, which we have always ascribed to the “pull of the earth,” was reinterpreted the other day by a scientist who says that when we fall it is not earth pulling us, it is heaven pushing us. This blasts the rock on which we sit. If science can do a rightabout-face on a thing as fundamental as gravity, maybe Newton was a sucker not to have just eaten the apple.

Man is a seed and the world is his apple; and just as the seed fares in the apple, so does man fare in the world, which surrounds him.

Meteorology has ever been an apple of contention, as if the violent commotions of the atmosphere induced a sympathetic effect on the minds of those who have attempted to study them.

Newton lay 'neath a lofty palm tree,
When a coconut smashed on his knee.
“I realize so painfully,
The mystery of gravity.”
A coconut, not an apple, inspired his theory.

Newton’s passage from a falling apple to a falling moon was an act of the prepared imagination. Out of the facts of chemistry the constructive imagination of Dalton formed the atomic theory. Davy was richly endowed with the imaginative faculty, while with Faraday its exercise was incessant, preceding, accompanying and guiding all his experiments. His strength and fertility as a discoverer are to be referred in great part to the stimulus of the imagination.

NEWTONIAN, adj. Pertaining to a philosophy of the universe, invented by Newton, who discovered that an apple will fall to the ground, but was unable to say why. His successors and disciples have advanced so far as to be able to say when.

Of all the trees that have ever been cultivated by man, the genealogical tree is the driest. It is one, we may be sure, that had no place in the garden of Eden. Its root is in the grave; its produce mere Dead Sea fruit—apples of dust and ashes.

One day in the year 1666 Newton had gone to the country, and seeing the fall of an apple, [as his niece (Mme Conduit) told me,] let himself be led into a deep meditation on the cause which thus draws every object along a line whose extension would pass almost through the center of the Earth.

Our knowledge of the external world must always consist of numbers, and our picture of the universe—the synthesis of our knowledge—must necessarily be mathematical in form. All the concrete details of the picture, the apples, the pears and bananas, the ether and atoms and electrons, are mere clothing that we ourselves drape over our mathematical symbols— they do not belong to Nature, but to the parables by which we try to make Nature comprehensible. It was, I think, Kronecker who said that in arithmetic God made the integers and man made the rest; in the same spirit, we may add that in physics God made the mathematics and man made the rest.

Perhaps ’twas an apple fell from a tree,
That inspired young Isaac, to see.
  The law of gravity it sparked,
  A breakthrough, it marked,
And physics was changed, eternally!

Plant the Crab-Tree where you will, it will never bear Pippins.

Science is, perhaps, some kind of cosmic apple juice from the Garden of Eden. Those of it are doomed to carry the burden of original sin.

Sometime in my early teens, I started feeling an inner urgency, ups and downs of excitement and frustration, caused by such unlikely occupations as reading Granville’s course of calculus ... I found this book in the attic of a friend’s apartment. Among other standard stuff, it contained the notorious epsilon-delta definition of continuous functions. After struggling with this definition for some time (it was the hot Crimean summer, and I was sitting in the shadow of a dusty apple tree), I got so angry that I dug a shallow grave for the book between the roots, buried it there, and left in disdain. Rain started in an hour. I ran back to the tree and exhumed the poor thing. Thus, I discovered that I loved it, regardless.

Such is always the pursuit of knowledge. The celestial fruits, the golden apples of the Hesperides, are ever guarded by a hundred-headed dragon which never sleeps, so that it is an Herculean labor to pluck them.

The first acquaintance which most people have with mathematics is through arithmetic. That two and two make four is usually taken as the type of a simple mathematical proposition which everyone will have heard of. … The first noticeable fact about arithmetic is that it applies to everything, to tastes and to sounds, to apples and to angels, to the ideas of the mind and to the bones of the body.

The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.

The symbol A is not the counterpart of anything in familiar life. To the child the letter A would seem horribly abstract; so we give him a familiar conception along with it. “A was an Archer who shot at a frog.” This tides over his immediate difficulty; but he cannot make serious progress with word-building so long as Archers, Butchers, Captains, dance round the letters. The letters are abstract, and sooner or later he has to realise it. In physics we have outgrown archer and apple-pie definitions of the fundamental symbols. To a request to explain what an electron really is supposed to be we can only answer, “It is part of the A B C of physics”.

There is nothing in the world more peaceful than apple-leaves with an early moon.

There were taken apples, and … closed up in wax. … After a month's space, the apple inclosed in was was as green and fresh as the first putting in, and the kernals continued white. The cause is, for that all exclusion of open air, which is ever predatory, maintaineth the body in its first freshness and moisture.
[In the U.S., since the 1920s, (to replace the fruit's original wax coating that is lost in the cleaning process after harvesting), natural waxes, such as carnauba wax, are applied in an extremely thin coating, to reduce loss of moisture and maintain crispness and appearance.]

Three apples changed the world, Adam's apple, Newton's apple, and Steve's apple.
[Tweeted tribute for Steve Jobs, co-founder the Apple computer company.]

Well, evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world’s data. Theories are structures of ideas that explain and interpret facts. Facts do not go away while scientists debate rival theories for explaining them. Einstein’s theory of gravitation replaced Newton’s, but apples did not suspend themselves in mid-air pending the outcome. And human beings evolved from apelike ancestors whether they did so by Darwin’s proposed mechanism or by some other, yet to be discovered … Evolutionists make no claim for perpetual truth, though creationists often do (and then attack us for a style of argument that they themselves favor).

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.

When you look at the companies that have really won customers over in technology—say, Apple and Google—you find that they spend billions of dollars on R&D [research and development] each year, often spending that much on a product before they ever make a dime back in profits. Unfortunately, in the environment, I don’t see as much willingness to invest heavily in R&D as I do in consumer technology. And that’s a pity.