the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
October 29, 1929  The Wall Street crash occurs, starting the Great Depression.
October 29, 1998  Hurricane Mitch causes much destruction in Central America.
October 31, 1517  Protestant Reformation: Martin Luther is believed to have nailed his 95 theses to Wittenberg Castle Church in Germany on this date.
October 31, 1984  Prime Minister of India Indira Gandhi is shot dead by two Sikh security guards.
Riots against the Sikh population start soon after.
October 31, 2011  The population of the world is said to have officially reached seven billion on this date.
Because Daylight Saving Time ends in October in some Northern Hemisphere countries, it is sometimes seen as the "longest" month there.
in a common year, October 31 falls on the same day of the week as February 28 while in a leap year, it falls on the same day of the week as February 29.
October 1 is the only day in October to start within the third quarter of the calendar year.
This month is tied with November as the months with the most births of US Presidents as of January 20, 2021: with six - Jimmy Carter (October 1), Rutherford B. Hayes (October 4), Chester A. Arthur (October 5), Dwight D. Eisenhower (October 14), Theodore Roosevelt (October 27) and John Adams (October 30).
October's flower is the Calendula.
One of October's birthstones is the opal.
The meaning of the opal is hope.
The other birthstone of October is the pink tourmaline.
The astrological signs for October are Libra (September 22 to October 21) and Scorpio (October 22 to November 21).
Octobre in easy French
Of is a preposition used in the English language to show a possessive relationship.
For example, the phrase "book of maps" means that the book has maps.
The phrase "father of Mike" means the father that is being mentioned is Mike's father.
One (1) is the first natural number, followed by two.
The Roman numeral for one is I.
In mathematics, 1 is the multiplicative identity.
It is sometimes called the "unity".
It is also the only number for which these special facts are true:
Any number  multiplied by 1 equals that number: .
For example, .
Any number  divided by 1 equals that number: .
Any number , other than 0, divided by itself always equals 1: .
For example: .
1 cannot be divided by any other number bigger than itself so that the result is a natural number.
In mathematics, 0.999... is a repeating decimal that is equal to 1.
Many proofs have been made to show this is correct.
The number one is important for computer science, because the binary numeral system uses only 1s and 0s to represent numbers.
In machine code and many programming languages, one means "true" (or "yes") and zero means "false" (or "no").
In Germany and Austria, one is the grade for "very good".
It is the best grade of six possible grades in Germany, and the best of five possible grades in Austria.
In the Netherlands, one is the lowest grade, and ten the highest.
In Poland, one is also the lowest grade, but the highest is six.
In numerology, the number one is a symbol for everything (unity), the beginning, and God.
Calixa Lavallée wrote the music; Adolphe-Basile Routhier wrote the words in French.
It was first sung in French in 1880.
Robert Stanley Weir wrote English words for the song in 1908.
Our home and native land,
True patriot love in all of us command!
With glowing hearts we see thee rise
The True North strong and free,
O Canada, we stand on guard for thee;
("Canada, our home and the country where we were born, everything we do is for you!
With joy we watch you get better and better.
You are the True North, strong and free.
Our citizens come from all over the earth and we watch over you to keep you safe.
God, please keep our land good and free!
O Canada, we watch over you to keep you safe.")
Here are the words in French.
The words in French and English do not mean the same thing.
Ô Canada!
Terre de nos aïeux,
Ton front est ceint de fleurons glorieux!
Et ta valeur de foi trempée
Protégera nos foyers et nos droits;
("Canada, land of our parents and grandparents, you wear a crown of beautiful flowers!
You can carry a sword, and you can carry a cross (for Christianity); your whole history is full of the great things you have done.
You are brave and faithful, and this will protect our homes and our rights.")
Oahu (or Oʻahu) is the third largest of the Hawaiian Islands, in the United States.
It means "the gathering place" (a place where people meet) in the Hawaiian language.
Most of the people of Hawaii live there (1.2 million of the state's 1.7 million in the mid-1990s).
The total land area is .
Honolulu, the capital city of Hawaii, is on this island.
Other well-known places on Oahu are Waikiki, Pearl Harbor, Diamond Head, Hanauma Bay, Kaneohe Bay, and both the North Shore and Makaha (which are famous for very big ocean waves).
Kamehameha I made Oahu his capital when he became the first king of Hawaii.
Iolani Palace was built later on by others of the royal family.
It is the only royal palace on American soil.
Oahu was perhaps the first of the Hawaiian Islands which the crew of HMS Resolution saw on 18 January 1778.
This was during Captain James Cook's third Pacific Ocean trip.
Europeans did not land on Oahu until 28 February 1779 when Captain Clerke of the HMS Resolution stepped ashore at Waimea Bay.
Clerke took command of the ship after Captain Cook was killed at Kealakekua Bay on February 14.
Today, Oahu has become a tourism and shopping center.
Almost 7 million visitors (mainly from the American mainland and Japan) go there every year to enjoy the special island holiday found only in Hawaii.
Oahu in TV
Oahu can be seen in hundreds of movies and TV shows.
Some of them are Magnum, P.I., Lost, Hawaii Five-O and Jake and the Fatman.
Open content is when someone creates something and lets others copy it or change it without having to ask for permission.
Any media can be open content, from text and pictures to video and sound.
When someone creates something (like a picture or book), they can make that work "open".
This means that other people are allowed to copy it and change it if they want.
Something that is open content may be free of charge, but it does not have to be.
The Simple English Wikipedia is open content.
So are other Wikipedias.
If a person changes open content or makes new open content, everyone can give it to anyone else, or even sell it.
It is never needed to ask permission to do this, because the people who wrote the text already gave their permission when they clicked the "save" button.
The rules that say how people can use, change and pass around open content are called a license.
A license explains exactly what you are allowed to do with the content that falls under it.
Licenses are often written in difficult language (legal jargon), but many licenses have summaries that are much easier to understand.
The makers of open content get to choose what license to use for their work, and everyone else has to follow it.
Only the maker, who owns the copyright, can change it to another license.
Most open content licenses say that when others change the work, they must also declare it to be open and under the same license.
This is called share-alike and means that anything based on work will always be open content.
All the content in Wikipedia is open under the rules of the Creative Commons Attribution/Share-Alike License, a very well-known open content license.
Another well-known open content license is the GNU Free Documentation License.
Content license
Orthography is an official or correct way to write a particular language.
It includes rules of spelling.
Orthography may also include rules about punctuation, capitalization, and diacritics (e.g. accents).
In English, spelling is a problem for all learners, and is the main issue in orthography.
Some languages have someone to decide the correct spelling, such as the Académie française.
English does not.
English orthography was the work of the early printers.
They had to decide how particular words would be spelled in their books.
Gradually the number of alternative spellings began to drop.
The word which is "merry" today was spelled in about 30 ways in written sources from the 9th to the 16th century.p970
English orthography
English orthography, or English spelling, is the way the 26 letters of the alphabet are used to write down the 36 (IPA) sounds of English.
The first manuscripts in Old English were written using the Latin alphabet.
It had 24 letters.p16
No alphabet fits its language exactly.
One reason for this is that there are always more sounds than letters.
In English there are far more vowel sounds than vowels.
The ancient Greeks, who were the first to use letters for vowels, decided to use only a few letters for their vowel sounds.
This choice influenced all later alphabets:
"The importance of the Greeks in the history of alphabetic writing is paramount.
All the alphabets in use in Europe today stand in direct or indirect relation to the ancient Greek".
English would need about 20 vowels to represent the vowel phonemes (~sounds) in common use,p237 and some languages do have more letters for vowels.
The Georgian language has a total of 41 letters.
A shorter alphabet works by using two or three letters for a single sound, or one letter for several sounds.
The other reason that alphabets never exactly fit languages is dialect.
A spoken language varies from place to place and from time to time.
This is very obvious with English, as the pronunciation is so different in different parts of the world.
A written language will always be less flexible than its spoken parent.
It has a different function, and is produced mechanically.
It must serve everyone who speaks the language, and it does this by keeping the spelling similar from one time to another.
Therefore, all alphabets have sounds which are difficult to represent with the letters in use.
And English also has other problems: sounds that can be written in different ways, and spelling which can be pronounced in different ways.
This all gives rise to problems of spelling.
British and American English
Differences between American English and British English spelling came about mainly as the result of one man.
Noah Webster (1758–1843) wrote a Grammar, a Spelling book, and finally an American dictionary of the English language.
In the course of this, he proposed a number of simplifications in spelling.
In his dictionary, he chose s over c in words like defense, he changed the re to er in words like center, he dropped one of the Ls in traveler.
At first he kept the u in words like colour or favour but dropped it in later editions.
He also changed tongue to tung: that did not stick.
His main reason was to help children learn to read and write.
Webster's dictionary contained seventy thousand words, of which twelve thousand had never appeared in a published dictionary before.
Webster did create a slightly different identity for American English.
But, because his efforts did not address some of the most glaring problems, his variations make little difference to the way the language is used.
An example of the real problems in English orthography is the word ending -ough, which is pronounced several different ways: tough, bough, cough...  The root causes of spelling variation are historical.
Loan words come with their own (foreign) spelling.
Some French loan words are still spelled in the French way; others have been changed.
English spelling reform has been proposed by many people since Webster, such as George Bernard Shaw, who proposed a new phonetic alphabet for English.
In some cases Webster's changes have been widely adopted in Britain: the spelling programme came from the French; US program is clearly simpler, and more consistent with word endings in English.
In our modern world, English orthography is still a problem.
In some countries (notably, France) a national committee can give advice and direction as to spelling.
English has long escaped from national custody.
Spelling, though important, is less important than how the language is used in practice.
The differences between British and American English in use are more to do with idiom, slang and vocabulary than they are to do with spelling.
In this respect, spelling in writing or print is a bit like pronunciation in speech.
They are the necessary outer clothes, but the inner substance is more important.
In Wikipedia (note the spelling), articles may be in either American or British English, but should be consistent within each article.
More details: Wikipedia:Manual of Style
Dictionaries and phonetics
Modern British spelling and use was greatly influenced by the two great English dictionaries, Samuel Johnson's A dictionary of the English language (1755), and James Murray's Oxford English Dictionary.
Johnson's dictionary was hugely influential, abroad as well as at home.
The dictionary was exported to America.
"The American adoption of the Dictionary was a momentous event not just in its history, but in the history of lexicography.
For Americans in the second half of the eighteenth century, Johnson was the authority on language, and the subsequent development of American dictionaries was coloured by his fame".p224
"America's two great nineteenth-century lexicographers, Noah Webster and Joseph Emerson Worcester, argued fiercely over Johnson's legacy ... In 1789 [Webster] declared that 'Great Britain, whose children we are, and whose language we speak, should no longer be our standard; for the taste of her writers is already corrupted, and her language on the decline.' ...
Where Webster found fault with Johnson, Joseph Worcester saluted him ... In 1846 he completed his Universal and critical dictionary of the English Language.p226
Some people argue which language is the easiest to spell.
People who learn a second language tend to think that their first (native) language is the easiest.
However, for the learner, programmatic languages, with well-defined rules, are easier to start with than English.
The spelling of the English language is by far the most irregular of all alphabetic spellings and thus the most difficult to learn.
English is, in its origin, a Germanic language.
From its early roots as Anglo-Saxon, it has borrowed words from many other languages: French (a Romance language) and Latin are the most frequent donors to English.
Languages that use phonetic spelling are easier to learn to spell than others.
With phonetic spelling the words are spelled as they are pronounced.
The Italian word "orologio" for instance is pronounced oh-ro-LO-jo ("gi" always making a "j" sound.)
In English, one comes across the word "knife".
In "knife", the "k" is not spoken, even though in English it's more common to pronounce "K"s when they are in words.
History of English spelling
One of the problems we have is that similar sounding words may be spelt quite differently.
Rough and ruff; meet and meat; great and grate.
Words with complicated spelling may be pronounced simply: Leicester is pronounced 'Lester'.
Even what rules we do have are frequently broken. "
i before e except after c" has over 100 exceptions.p272 Almost all these problems have come about for historical reasons.
English has been changing for the last thousand years, and as the language changes, so parts of it get stuck with different spellings.
Originally a 23-letter alphabet for the 35 or so phonemes (sounds) of Old English.
Other letters were added later.
After the Norman conquest, French scribes introduced new spellings.
Many of the early printers came from the continent of Europe, and brought other spelling norms to England.
But, although print stabilised spelling, pronunciation continued to change.
Printing coincided with the Great Vowel Shift at the end of Middle English (end 14th to 15th centuries).
To avoid complex details, here is what happened: over a century, the pronunciation of all the vowels changed, and is still not standard throughout Britain.
In any event, the spelling of thousands of words now reflects their pronunciation in Geoffrey Chaucer's time.
16th-century scholars tried to indicate the history of a word by its spelling: the silent 'b' in 'debt' is there to reflect the Latin debitum.
More loan words added in the late 16th to early 17th century, such as pneumonia, idiosyncrasy, epitome, cocoa.
English has a huge number of words, but its spelling comes from many different sources. "
The large and varied lexicon of English has been bought at the expense of an increasingly deversified graphology".p275
Differences between languages
Some languages have a high correspondence between phonemes and letters.
That means they get close to one letter for each sound.
If there was a perfect correspondence, that language would have phonemic orthography.
English is highly non-phonemic.
It has almost every kind of deviation known:
different letters for the same sound
two or more letters for a single sound
sound depends on nearby letters
vast range of words whose sound varies according to dialect
huge number of loan words with imported spellings
defective: it does not represent some important differences in phonemes.
Example: the difference between the voiced th (the) and the unvoiced th (thin).
This field of study is called "orthographic depth".
The orthographic depth of an alphabetic script is the degree to which a written language deviates from simple one-to-one letter–phoneme correspondence.
It shows how easy it is to predict the pronunciation of a word from its spelling.
Shallow orthographies are easy to pronounce based on the written word, and deep orthographies are difficult to pronounce based on how they are written.
In shallow orthographies, the spelling-sound correspondence is direct: given the rules of pronunciation, one is able to "say" the word correctly.
Most other international languages have similar problems: in French, Arabic or Hebrew, new readers have difficulty learning to decode words.
As a result, children learn to read more slowly.
In both Spanish and Italian there is a more direct connection between spelling and pronunciation.
Those are languages with low orthographic depth.
The word oil is used for many different kinds of liquids.
Oil usually does not mix with water.
Vegetable oils are made from plants.
Many are used in foods and for cooking.
Some kinds of plant oils that people use are palm oil, maize (corn), olive, peanut, soy, and sunflower.
Other kinds of oil are made from crude oil (petroleum) which comes from under the ground.
People use large oil wells to bring the oil up to the surface.
The oil is sent in special ships called tankers or in pipelines to factories called refineries where it is distilled into LPG, gasoline (petrol), diesel fuel, and fuel oil.
Plastics are among the Petrochemicals made from crude oil or natural gas.
Oils from crude oil are also used as fuels for engines or as lubricants to make the parts of machines work together without sticking or stopping.
Different kinds of oils are also used for many other things, for example to make cosmetics, medicines, paints, and detergents, like washing up liquids.
Soap(s) are similar to detergents, but they are generally made from animal fat(s) rather than oils.
OK (okay) is a word in the English language.
It is used to mean that something is good or correct.
It is the opposite of the word bad.
It can often be used instead of the word Yes.
It is not certain where the word "OK" originally comes from, but some experts say it came from a funny way of writing "Ol Korrect" (All correct).
You also find the phrase "Ola kala" in Greek, which means 'All Correct".
For Example:
I think it is 'ok' to present this project in our office.
The term appears to have achieved prominence in the United States in 1840, when supporters of the American Democratic political party claimed during the 1840 United States presidential election that it stood for "Old Kinderhook," a nickname for a Democratic presidential candidate, Martin Van Buren, a native of Kinderhook, New York. "'
Vote for OK' was snappier than using his Dutch name."
In response, Whig opponents attributed OK, in the sense of "Oll Korrect," to Andrew Jackson's bad spelling.
The country-wide publicity surrounding the election appears to have been a critical event in okay's history, widely and suddenly popularizing it across the United States.
An oxymoron  is a term for a figure of speech.
It is made up of two or more words that seem to be opposite to each other, or actually are opposite.
For example, the phrases "Wise fool", "Warm freezer", and "Legal murder" all have two words.
In each one, the one word looks like the opposite of the other word.
You can have words that look opposite, but are right.
For example, a "warm freezer" could be right.
A freezer could be warm if it was turned off or left open.
Words that really are opposite to each other, would be words that just cannot be put together.
For example, a "round square" could not happen because squares are not round.
Oxymorons sometimes appear in jokes.
Sometimes, the joke is just to say that a pair of words are an oxymoron.
For example, a joke that says that "glutted peasant" is an oxymoron.
This means that peasants are usually hungry, if the word 'peasant' is opposite to 'glutted'
An operating system (or OS) is a group of computer programs, including device drivers, kernels, and other software that lets people interact with a computer.
It manages computer hardware and software resources.
It provides common services for computer programs.
An OS can be small (like MenuetOS), or large (like Microsoft Windows).
Different operating systems can be used for different purposes.
Some are used for everyday things like on a personal computer.
Others are mobile operating systems or are used for specialized work.
An operating system has many jobs.
It makes sure that all the programs can use the CPU, system memory, displays, input devices, and other hardware.
Some also give the user an interface to use a computer.
An OS is also responsible for sending data to other computers or devices on a network.
The first operating system was used with the ENIAC (Electronic Numerical Integrator and Computer).
It was very hard to make ENIAC do work.
How the operating system worked was based on how the switches and cables were put together and depending on this factor punch cards would make a result.
While this was an operating system of a kind, it is not what is thought of as one in modern times.
The first operating system that looked and felt like operating systems in the modern age was UNIX, made in 1969 by Bell Labs.
It had a small kernel and many tiny programs that could be put together to work with user input and data.
Many of its features were taken from Multics, an older operating system made in 1964.
Single- and multi-tasking
A single-tasking system can only run one program at a time.
A multitasking operating system can run more than one program at the same time.
Multi-tasking is done by dividing processor time.
The processor gives a little bit of its time to each program.
Single- and multi-user
Single-user operating systems cannot distinguish between users, but may allow multiple programs to run simultaneously.
A multi-user operating system permits multiple users to interact with the system at the same time.
A distributed operating system manages a group of distinct computers and makes them appear to be a single computer.
Distributed computations are carried out on more than one machine.
In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine as a guest operating system, then saving it as a tool for multiple running virtual machines.
The technique is common in large server warehouses.
Embedded operating systems are designed to be used in embedded systems.
They are designed to operate on small machines like PDAs with less autonomy and are able to operate with a limited number of resources.
A real-time operating system guarantees processing of events or data by a specific moment in time.
A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved.
An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
Philosophy is the study of underlying things.
This means philosophy tries to understand the reasons or basis for things.
It also tries to understand how things should be. ""
is the Ancient Greek word for the "love of wisdom".
A person who does philosophy is called a philosopher.
A philosopher is a kind of thinker or researcher.
A "philosophy" can also mean a group of ideas by philosophers, or by a philosopher.
Philosophy is a way of thinking about the world, the universe, and society.
In the past, sciences were part of philosophy as well.
The ideas in philosophy are often general and abstract.
But this does not mean that philosophy is not about the real world.
Ethics, for example, asks about how to be good in our day-to-day lives.
Metaphysics asks about how the world works and what it is made of.
Sometimes people talk about how they have a ‘personal philosophy’, which means the way a person thinks about the world.
This article is not about people's ’personal philosophies’.
This article is about the ideas that have been discussed by philosophers (people who think and write about ways of thinking) for a long time.
One philosophical question is this: "Is there any knowledge in the world which is so certain that no reasonable man could doubt it?".
Other questions asked by philosophers are these:
what should we do in our lives?
What happens to a soul after death, how does a soul enter into the body before death?
Why should we live?
Why are there so many hurdles in life?
How do we overcome suffering?
What is the importance of the material life?
Will the universe exist forever?
Does the world around us exist?
What is the relationship between mind and body?
The etymological meaning of the word 'Philosophy' is 'love of wisdom'.
It comes from the Greek word 'Philosophia', with 'Philo' meaning 'beloved' and 'Sophia' meaning 'wisdom.
There are different types of philosophy from different times and places.
Some philosophers came from Ancient Greece, such as Plato and Aristotle.
Others came from Asia, such as Confucius or Buddha, or Adi  Shankara and Laozi.
Some philosophers are from the Middle Ages in Europe, such as William of Ockham or Saint Thomas Aquinas.
Philosophers from the 1600s, 1700s, and 1800s included Thomas Hobbes, René Descartes, John Locke, David Hume, and Immanuel Kant.
Philosophers from the 1900s included Søren Kierkegaard, Ludwig Wittgenstein, and Jean-Paul Sartre.
Areas of inquiry Philosophy is the study of humans and the world by thinking and asking questions.
It is a science and an art.
Philosophy tries to answer important questions by coming up with answers about real things and asking "why?"
Sometimes, philosophy tries to answer the same questions as religion and science.
Philosophers do not all give the same answers to a question.
Many types of philosophy criticize or even attack the beliefs of science and religion.
In his work Critique of Pure Reason,  Immanuel Kant asked the following questions:
What dare I hope?
Categories in philosophy
Philosophy can be divided into different groups, based on the types of questions that it asks.
Below is a list of questions split into groups.
One possible list of answers to these questions can be called a 'philosophy'.
There are many different 'philosophies', because all of these questions have many different answers according to different people.
Not all philosophies ask the same questions.
These are the questions that are usually asked by philosophers from the Western world:Metaphysics:
Ontology:
What is the world that we see around us? (
What is reality?)
Is there more to the world than just what we see or hear?
If nobody sees something happening, does that mean that it did not happen?
What does it mean to say that something is possible?
Do other worlds exist?
Is there anything very special about being a human being or being alive at all?
If not, why do some people think that there is?
What is space?
The philosophy of mind:
What is a mind?
What is a body?
Do people make choices, or can they only choose to do one thing? (
Do people have free will?)
What makes words or ideas meaningful? (
What is the relation between meaningful words or ideas and the things that they mean?)
The philosophy of religion:
Do people have souls?
Is there a God who created the Universe?In epistemology:
How can we know anything?
What is truth?In ethics:
What are right and wrong, good and bad?
Should people do some things and not others?
What is justice?In aesthetics:
What if one person thinks a painting is beautiful, but another person thinks the painting is ugly?
Can the painting be beautiful and ugly at the same time?
Are true things beautiful?
Are good things beautiful?
We commonly think that a sculpture in a museum is art.
If a sculptor sculpts a sculpture of a rock from clay, and puts it in a museum, many would call it art.
But what if a person picks up a rock from the ground - is the rock a piece of art?In logic:
What do the words we use mean?
How can we say things (especially ideas) in a way that only has one meaning?
Can all ideas be expressed using language?
How does the truth of an argument's premise affect the truth of its conclusion?
How can we reason correctly?In axiology''':
What has value?
Is time really money?
or have we made it so?
Does love, beauty, or justice hold any value?
Other divisions include eschatology, teleology and theology.
In past centuries natural science was included in philosophy, and called "natural philosophy".
Is philosophy good or bad?
Does philosophy do any good?
Very few people would dispute this.
It is easy to argue that philosophy is a good thing, because it helps people to think more clearly.
Philosophy helps people to understand the world and the way people act and think.
Philosophers believe that asking philosophical questions is useful because it brings wisdom and helps people to learn about the world and each other.
Some philosophers might even argue that the question "Is philosophy good or bad?"
is a philosophical question itself.
However, some people think that philosophy is harmful, as philosophy encourages free-thinking and often questions the beliefs that others hold.
For example, philosophies such as some existentialist views say that there is no meaning to life or human existence, except the meaning that we make up or invent.
People from some religions do not agree with the beliefs of existentialism.
Every major science, including physics, biology, and chemistry, are disciplines that were once considered as philosophy.
Medicine was always considered a practical art, however.
As facts about nature became more understood, these subjects branched away.
Psychology only split a century and a half ago.
In our own time, subjects such as consciousness studies, decision theory, and applied ethics have increasingly found independence from philosophy as a whole.
Because of this, philosophy seems useful because it spins off new kinds of science.
What philosophers do
Philosophers ask questions about ideas (concepts).
They try to find answers to those questions.
Some thinkers find it very hard to find those words that best describe the ideas they have.
When they find answers to some of these questions philosophers often have the same problem, that is how to best tell the answers they found to other people.
Depending on the meaning of the words they use, the answers change.
Some philosophers are full-time thinkers (called academics), who work for universities or colleges.
These philosophers write books and articles about philosophy and teach classes about philosophy to university or college students.
Other philosophers are just "hobby" thinkers who think about philosophy during their free time.
A small number of hobby thinkers have thought so much about philosophy that they are able to write articles for philosophy magazines.
Other people approach philosophy from another job.
For example, monks, artists, and scientists may think about philosophical ideas and questions.
Some philosophers say the only thing needed to answer a question is to find out what it means.
The only thing that makes philosophical questions (such as those above) difficult is that people do not really know what they mean.
Ludwig Wittgenstein believed this.
Philosophers often use both real and imaginary examples to make a point.
For example, they may write about a real or fictional person in order to show what they think a good person or a bad person is like.
Some philosophers look for the simplest way to answer a question and say that is probably the right answer.
This is a process called Occam's razor.
Others believe that complicated answers to questions can also be right.
For an example of a philosophical problem, see the God paradox.
Philosophers use logic to solve problems and answer questions.
Logical consistency is a cornerstone of any acceptable theory.
Philosophers who disagree with a theory will often try to find a logical contradiction in a theory.
If they find a contradiction, this gives them a reason to reject that theory.
If they do not find an inconsistency, the philosopher might show that the theory leads to a conclusion which is either unacceptable or ridiculous.
This second approach is usually called reductio ad absurdum.
Some philosophers
People listed here should be genuine philosophers, rather than social or political campaigners.
The lists are not meant to be complete.
The ancient Greek philosophers
Later European/Western philosophers
Saint Augustine
Duns Scotus
Georg Wilhelm Frederich Hegel
Modern European and American philosophers
G. E. M. Anscombe
Christian DeQuincey
Latin American and Latina/o philosophers
Sor Juana Inez de la Cruz
Ofelia Schutte
Eugenio María de Hostos
Asian/Eastern philosophers
Siddhārta Gautama (the Gautama Buddha)
Nanak
Sohrevardi
Allama Iqbal
General sources
Philosophy and living.
Craig, Edward.
Philosophy: a very short introduction.
Harrison-Barbet, Anthony.
Mastering philosophy.
Russell, Bertrand.
The problems of philosophy.
Sinclair, Alistair J.  2008.
An introduction.
Sober, Elliott 2001.
Core questions in philosophy: a text with readings.
Upper Saddle River, Prentice Hall.
Solomon, Robert C. Big questions: a short introduction to philosophy.
Warburton, Nigel.
Philosophy: the basics.
Nagel, Thomas.
A very short introduction to philosophy.
Pojman, Louis P.  Classics of Philosophy (vols.
1, 2, & 3)
Arthur, Edwin  The English Philosophers from Bacon to Mill
Beardsley, Monroe  European Philosophers from Descartes to Nietzsche
Cottingham, John 2008.
Western philosophy: an anthology.
Malden, MA: Blackwell Pub., .
Tarnas, Richard.
The passion of the Western mind: understanding the ideas that have shaped our world view''.
The School of Life on YouTube
Einzelgänger (In search of) on YouTube
It is one of the most fundamental scientific disciplines.
The main goal of physics is to explain how things move in space and time and understand how the universe behaves.
It studies matter, forces and their effects.
The word  physics comes from the Greek word ἡ φύσις, meaning "nature".
Physics can also be defined as "that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events".
Physics is very important in the development of new technologies, such as airplanes, televisions, computers and nuclear weapons.
Mechanics, a branch of physics, helped develop the mathematical field of calculus.
Astronomy, a part of physics, is the oldest natural science.
In the past it was a part of 'natural philosophy' with other fields of science, such as chemistry and biology.
During the scientific revolution, these fields became separate, and physics became a distinct field of knowledge.
Ancient astronomy
Astronomy is the oldest natural science.
The Sumerians, and Ancient Egyptians studied the stars, mostly with a view to prediction and religion.
The first Babylonian star maps date from about 1200 BC.
That astronomical events are periodic also dates back to the Babylonians.
Their understanding was not scientific, but their observations influenced later astronomy.
Much astronomy came from Mesopotamia, Babylonia, Ancient Egypt, and Ancient Greece.
Astronomers from Egypt built monuments that showed how objects in the sky moved, and most of the names for the constellations in the Northern hemisphere came from Greek astronomers.
Natural philosophy
Natural philosophy started in Greece around 650 BC when a movement of philosophers replaced superstition with naturalism, which refuted the spiritual.
Leucippus and his student Democritus suggested the idea of the atom around this period.
Physics in the medieval Islamic world
Islamic scholars continued to study Aristotelian physics during the Islamic Golden Age.
One main contribution was to observational astronomy.
Some, like Ibn Sahl, Al-Kindi, Ibn al-Haytham, Al-Farisi and Avicenna, worked  on optics and vision.
In The Book of Optics, Ibn al-Haytham rejected previous Greek ideas concerning vision and proposed a new theory.
He studied how light enters the eye, and  developed the camera obscura.
European scientists later built eyeglasses, magnifying glasses, telescopes, and cameras from this book.
Physics became a separate field of study after the scientific revolution.
Galileo's experiments helped to create classical physics.
Although he did not invent the telescope, he used it when he looked into the night sky.
He supported Copernicus' idea that the Earth moved around the Sun (heliocentrism).
He also investigated gravity.
Isaac Newton used Galileo's ideas to create his three laws of motion and his law of universal gravitation.
Together these laws explained the motion of falling bodies near the earth and the motion of earth and planets around the sun.
In a couple centuries, the Industrial Revolution was in full swing and many more discoveries were made in many fields of science.
The laws of classical physics are good enough to study objects that move much slower than the speed of light, and are not microscopic.
When scientists first studied quantum mechanics, they had to create a new set of laws, which was the start of modern physics.
Modern physics
As scientists researched particles, they discovered what classical mechanics could not explain.
Classical mechanics predicted that the speed of light varied, but experiments showed the speed of light stayed the same.
This was predicted by Albert Einstein's theory of special relativity.
Einstein predicted that the speed of electromagnetic radiation through empty space would always be the same.
His view of space-time replaced the ancient idea that space and time were quite separate things.
Max Planck came up with quantum mechanics to explain why metal releases electrons when you shine a light at it, and why matter emits radiation.
Quantum mechanics applies for very small things like the electrons, protons, and neutrons that make up an atom.
People like Werner Heisenberg, Erwin Schrödinger, and Paul Dirac continued to work on quantum mechanics and eventually we got the Standard Model.
Physics is the study of energy and matter in space and time and how they are related to each other.
Physicists assume the existence of mass, length, time and electric current and then define (give the meaning of) all other physical quantities in terms of these basic units.
Mass, length, time, and electric current are never defined but the standard units used to measure them are always defined.
In the International System of Units (abbreviated SI from the French Système International), the kilogram is the basic unit of mass, the metre is the basic unit of length, the second is the basic unit of time, and the ampere is the basic unit of electric current.
Physics studies how things move, and the forces that make them move.
For example, velocity and acceleration are used by physics to show how things move.
Also, physicists study the forces of gravity, electricity, magnetism and the forces that hold things together.
Physics studies very large things, and very small things.
For instance, physicists can study stars, planets and galaxies but could also study small pieces of matter, such as atoms and electrons.
They may also study sound, light and other waves.
As well as that, they could examine energy, heat and radioactivity, and even space and time.
Physics not only helps people understand how objects move, but how they change form, how they make noise, how hot or cold they will be, and what they are made of at the smallest level.
In short, physics is the branch of science that deals with properties of matter and energy along with the interaction between them.
Physics and mathematics
Physics is a quantitative science because it is based on measuring with numbers.
Mathematics is used in physics to make models that try to predict what will happen in nature.
These predictions are compared to the way the real world works.
Physicists are always working to make their models of the world better.
Classical mechanics contains major topics such as Newton's laws of motion, Lagrangian mechanics, Hamiltonian mechanics, kinematics, statics, dynamics, chaos theory, acoustics, fluid dynamics, continuum mechanics.
Classical mechanics is all about forces acting on a body in nature, balancing forces, maintaining equlibrium state, etc .
Electromagnetism is study of charges on a particular body.
It contains subtopics such as Electrostatics, electrodynamics, electricity, magnetism, magnetostatics, Maxwell's equations, optics .
Thermodynamics and statistical mechanics are related with temperature.
It includes main topics such as Heat engine, kinetic theory.
It uses terms such as heat(Q), work(W), and internal energy (U).
First law of thermodynamics gives us the relation them by the following equation (ΔU = Q − W)
Quantum mechanics is the study of particle at the atomic level taking into consideration the atomic model.
It includes subtopics Path integral formulation, scattering theory, Schrödinger equation, quantum field theory, quantum statistical mechanics.
Advanced knowledge
Physics is the science of matter and how matter interacts.
Matter is any physical material in the universe.
Physics is used to describe the physical universe around us, and to predict how it will behave.
Breadth and goals of physics
The sweep of physics is broad, from the smallest components of matter and the forces that hold it together, to galaxies and even larger things.
There are only four forces that appear to operate over this whole range.
However, even these four forces (gravity, electromagnetism, the weak force associated with radioactivity, and the strong force which holds protons and neutrons in an atom together) are believed to be different parts of a single force.
One of the major goals of physics is making theories that apply to everything in the universe.
In other words, physics can be viewed as the study of those universal laws which define, at the most basic level possible, the behavior of the physical universe.
Physics uses the scientific method
Physics uses the scientific method.
That is, data from experiments and observations are collected.
Theories which attempt to explain these data are produced.
Physics uses these theories to not only describe physical phenomena, but to model physical systems and predict how these physical systems will behave.
Physicists then compare these predictions to observations or experimental evidence to show whether the theory is right or wrong.
The theories that are well supported by data and are especially simple and general are sometimes called scientific laws.
Of course, all theories, including those known as laws, can be replaced by more accurate and more general laws, when a disagreement with data is found.
Physics is quantitative
Physics is more quantitative than most other sciences.
That is, many of the observations in physics may be represented in the form of numerical measurements.
Most of the theories in physics use mathematics to express their principles.
Most of the predictions from these theories are numerical.
This is because of the areas which physics has addressed work better with quantitative approaches than other areas.
Sciences also tend to become more quantitative with time as they become more highly developed, and physics is one of the oldest sciences.
Fields of physics
Classical physics normally includes the fields of mechanics, optics, electricity, magnetism, acoustics and thermodynamics.
Modern physics is a term normally used to cover fields which rely on quantum theory, including quantum mechanics, atomic physics, nuclear physics, particle physics and condensed matter physics, as well as the more modern fields of general and special relativity, but these last two are often considered fields of classical physics as they do not rely on quantum theory.
Although this difference can be found in older writings, it is of little new interest as quantum effects are now understood to be of importance even in fields that before were called classical.
Approaches in physics
There are many ways to study physics, and many different kinds of activities in physics.
The two main types of activities are the collection of data, and the development of theories.
Some subfields of physics can be studied by experiment.
For example, Galileo Galilei invented kinematics by making experiments and studying the data.
Experimental physics focuses mainly on an empirical approach.
Some experiments are done to explore nature, and other experiments are performed to produce data to compare with the predictions of theories.
Some other fields in physics like astrophysics and geophysics are mostly observational sciences because most of their data has to be collected passively instead of through experimentation.
Galileo, for example, could only look at Jupiter and discover that it has moons.
However, observational programs in these fields use many of the same tools and technology that are used in the experimental subfields of physics.
Theoretical physics often uses quantitative approaches to develop the theories that attempt to explain the data.
In this way, theoretical physicists often use tools from mathematics.
Theoretical physics often can involve creating quantitative predictions of physical theories, and comparing these predictions quantitatively with data.
Theoretical physics sometimes creates models of physical systems before data is available to test and support these models.
These two main activities in physics, data collection, theory production and testing, use many different skills.
This has led to a lot of specialization in physics, and the introduction, development and use of tools from other fields.
For example, theoretical physicists use mathematics and numerical analysis and statistics and probability and computer software in their work.
Experimental physicists develop instruments and techniques for collecting data, using engineering and computer technology and many other fields of technology.
Often the tools from these other areas are not quite appropriate for the needs of physics, and need to be changed or more advanced versions have to be made.
Experimental physics, engineering and technology are related.
Experiments often need specialized tools such as particle accelerators, lasers, and important industrial applications such as transistors and magnetic resonance imaging have come from applied research.
Prominent physicists
Galileo Galilei (1564–1642)
Christiaan Huygens (1629–1695)
Isaac Newton (1643–1727)
Joseph Louis Lagrange (1736–1813)
Pierre-Simon Laplace (1749–1827)
Joseph Fourier (1768–1830)
Nicolas Léonard Sadi Carnot (1796–1842)
Rudolf Clausius (1822–1888)
James Clerk Maxwell (1831–1879)
J. Willard Gibbs (1839–1903)
Ludwig Boltzmann (1844–1906)
Hendrik A. Lorentz (1853–1928)
Henri Poincaré (1854–1912)
Nikola Tesla (1856–1943)
Max Planck (1858–1947)
Albert Einstein (1879–1955)
Milutin Milanković (1879–1958)
Emmy Noether (1882–1935)
Max Born (1882–1970)
Niels Bohr (1885–1962)
Erwin Schrödinger (1887–1961)
Louis de Broglie (1892–1987)
Satyendra Nath Bose (1894–1974)
Wolfgang Pauli (1900–1958)
Werner Heisenberg (1901–1976)
Paul Dirac (1902–1984)
Eugene Wigner (1902–1995)
Robert Oppenheimer (1904–1967)
Sin-Itiro Tomonaga (1906–1979)
Hideki Yukawa (1907–1981)
John Bardeen (1908–1991)
Lev Landau (1908–1967)
Anatoly Vlasov (1908–1975)
Nikolay Bogolyubov (1909–1992)
Subrahmanyan Chandrasekhar (1910–1995)
John Archibald Wheeler (1911–2008)
Richard Feynman (1918–1988)
Julian Schwinger (1918–1994)
Feza Gürsey (1921–1992)
Chen Ning Yang (1922– )