the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
The 'rungs' of the DNA ladder are each made of two bases, one base coming from each leg.
The bases connect in the middle: 'A' only pairs with 'T', and 'C' only pairs with 'G'.
The bases are held together by hydrogen bonds.
Adenine (A) and thymine (T) can pair up because they make two hydrogen bonds, and cytosine (C) and guanine (G) pair up to make three hydrogen bonds.
Although the bases are always in fixed pairs, the pairs can come in any order (A-T or T-A; similarly, C-G or G-C).
This way, DNA can write 'codes' out of the 'letters' that are the bases.
These codes contain the message that tells the cell what to do.
On chromosomes, the DNA is bound up with proteins called histones to form chromatin.
This association takes part in epigenetics and gene regulation.
Genes are switched on and off during development and cell activity, and this regulation is the basis of most of the activity which takes place in cells.
Copying DNA
When DNA is copied, this is called DNA replication.
Briefly, the hydrogen bonds holding together paired bases are broken and the molecule is split in half: the legs of the ladder are separated.
This gives two single strands.
New strands are formed by matching the bases (A with T and G with C) to make the missing strands.
First, an enzyme called DNA helicase splits the DNA down the middle by breaking the hydrogen bonds.
Then after the DNA molecule is in two separate pieces, another molecule called DNA polymerase makes a new strand that matches each of the strands of the split DNA molecule.
Each copy of a DNA molecule is made of half of the original (starting) molecule and half of new bases.
When DNA is copied, mistakes are sometimes made – these are called mutations.
There are four main types of mutations:
Deletion, where one or more bases are left out.
Substitution, where one or more bases are substituted for another base in the sequence.
Insertion, where one or more extra base is put in.
Duplication, where a sequence of bases pairs are repeated.
Mutations may also be classified by their effect on the structure and function of proteins, or their effect on fitness.
Mutations may be bad for the organism, or neutral, or of benefit.
Sometimes mutations are fatal for the organism – the protein made by the new DNA does not work at all, and this causes the embryo to die.
On the other hand, evolution is moved forward by mutations, when the new version of the protein works better for the organism.
Protein synthesis
A section of DNA that contains instructions to make a protein is called a gene.
Each gene has the sequence for at least one polypeptide.
Proteins form structures, and also form enzymes.
The enzymes do most of the work in cells.
Proteins are made out of smaller polypeptides, which are formed of amino acids.
To make a protein to do a particular job, the correct amino acids need to be be joined up in the correct order.
Proteins are made by tiny machines in the cell called ribosomes.
Ribosomes are in the main body of the cell, but DNA is only in the nucleus of the cell.
The codon is part of the DNA, but DNA never leaves the nucleus.
Because DNA cannot leave the nucleus, the cell nucleus makes a copy of the DNA sequence in RNA.
This is smaller and can get through the holes – pores – in the membrane of the nucleus and out into the cell.
Genes encoded in DNA are transcribed into messenger RNA (mRNA) by proteins such as RNA polymerase.
Mature mRNA is then used as a template for protein synthesis by the ribosome.
Ribosomes read codons, 'words' made of three base pairs that tell the ribosome which amino acid to add.
The ribosome scans along an mRNA, reading the code while it makes protein.
Another RNA called tRNA helps match the right amino acid to each codon.
History of DNA research
DNA was first isolated (extracted from cells) by Swiss physician Friedrich Miescher in 1869, when he was working on bacteria from the pus in surgical bandages.
The molecule was found in the nucleus of the cells and so he called it nuclein.
In 1928, Frederick Griffith discovered that traits of the "smooth" form of Pneumococcus could be transferred to the "rough" form of the same bacteria by mixing killed "smooth" bacteria with the live "rough" form.
This system provided the first clear suggestion that DNA carries genetic information.
In the 1950s, Erwin Chargaff  found that the amount of thymine (T) present in a molecule of DNA was about equal to the amount of adenine (A) present.
He found that the same applies to guanine (G) and cytosine (C).
Chargaff's rules summarises this finding.
In 1953, James D. Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal Nature.
Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image "Photo 51", taken by Rosalind Franklin and Raymond Gosling in May 1952.
Experimental evidence supporting the Watson and Crick model was published in a series of five articles in the same issue of Nature.
Of these, Franklin and Gosling's paper was the first publication of their own X-ray diffraction data and original analysis method that partly supported the Watson and Crick model; this issue also contained an article on DNA structure by Maurice Wilkins and two of his colleagues, whose analysis and in vivo B-DNA X-ray patterns also supported the presence in vivo of the double-helical DNA configurations as proposed by Crick and Watson for their double-helix molecular model of DNA in the previous two pages of Nature.
In 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine.
Nobel Prizes are awarded only to living recipients.
A debate continues about who should receive credit for the discovery.
How DNA was copied (the replication mechanism) came in 1958 through the Meselson–Stahl experiment.
More work by Crick and coworkers showed that the genetic code was based on non-overlapping triplets of bases, called codons.
These findings represent the birth of molecular biology.
How Watson and Crick got Franklin's results has been much debated.
Crick, Watson and Maurice Wilkins were awarded the Nobel Prize in 1962 for their work on DNA – Rosalind Franklin had died in 1958.
DNA and privacy concerns
Police in the United States used DNA and family tree public databases to solve cold cases.
The American Civil Liberties Union  raised concerns over this practice.
Human Genome Project: information
Karl Heinrich Marx (5 May 1818 in Trier – 14 March 1883 in London) was a German political thinker who wrote about economics and politics.
Marx thought that if a place that works together runs on wage-labor, then there would always be class struggle.
Marx thought that this class struggle would result in workers taking power.
He believed that no economic class—wage workers, land owners, etc.
should have power over another.
Marx believed that everyone should contribute what they can, and everyone should get what they need.
His most famous book was the Communist Manifesto.
He wrote it with Friedrich Engels in 1848.
The book is about the ideas and aims of communism.
His ideas are called Marxism.
His most important work is Das Kapital, or The Capital.
It is commonly known in English as simply 'Capital.'
He spent many years working on the three parts of the book.
Das Kapital describes how "capitalism" works and the problems this creates, such as division of labour, alienation and exploitation.
The book has led to many arguments between those who agree with the book and those who do not.
Marx's ideas have been thought of as responsible for socialist revolutions (like the Russian Revolution).
Marx's most popular theory was 'historical materialism', arguing that history is the result of material conditions, rather than ideas.
He believed that religion, morality, social structures and other things are all rooted in economics.
In his later life he was more tolerant of religion.
Marx also wrote the Economic and Philosophic Manuscripts of 1844, a critique of political economy in which he discusses topics such as labor wages, labor rent, and capital profit, and his ideas of how to change the economy, including proletarian socialist revolution and an eventual communist society.
Karl Marx was born in Trier in 1818, but he had to move many times because the government did not like his ideas.
Marx lived for a long time in London.
He died there in 1883.
After he died, his friend Engels finished many of his works.
Friedrich Engels' Biography of Marx
Franz Mehring's Karl Marx: The Story of His Life
Vladimir Lenin's Karl Marx Biography
Francis Wheen's Karl Marx: A Life
Karl Korsch's Karl Marx Biography
Maximilien Rubel's Marx, life and works
Articles and entries
Dead Sociologists - Karl Marx
Ernest Mandel, Karl Marx (New Palgrave article)
Marx on India and the Colonial Question  from anti-caste
Portraits of Karl Marx
The Karl Marx Museum
Marxmyths.org  - Various essays on misinterpretations of Marx
Paul Dorn, The Paris Commune and Marx' Theory of Revolution
Why Marx is the Man of the Moment
Bibliography and online texts
Critique of Hegel’s Philosophy of Right (1843)
On the Jewish Question (1843)
Notes on James Mill (1844)
Economic and Philosophical Manuscripts of 1844 (1844)
Theses on Feuerbach (1845)
The German Ideology [with Engels] (1845-46)
The Poverty of Philosophy (1846-47)
Wage-Labour and Capital (1847)
Manifesto of the Communist Party [with Engels] (1847-48)
Free audiobook from LibriVox (Also available in German)
The Eighteenth Brumaire of Louis Bonaparte (1852)
Grundrisse (1857-58)
A Contribution to the Critique of Political Economy (1859)
Writings on the U.S. Civil War [with Engels; compiled] (1861)
Theories of Surplus Value, 3 volumes (1862)
Value, Price and Profit (1865)
Capital vol.
1 (1867)
The Civil War in France (1871)
Critique of the Gotha Programme (1875)
Notes on Wagner (1883)
Capital, vol.
2 [posthumously, by Engels] (1893)
3 [posthumously, by Engels] (1894)
Letters [with Engels; compiled] (1833-95)
Ethnological Notebooks —  (1879-80)
"The Reality Behind Commodity Fetishism" (in English) at Sic et Non (in German)
Libertarian Communist Library Karl Marx Archive
Karl Marx Biography
Works by Karl Marx at Zeno.org
1818 births
1883 deaths
19th-century German philosophers
Former Christians
German atheists
German communists
German economists
German historians
German sociologists
Infectious disease deaths in London
Jewish atheists
Jewish German writers
Jewish philosophers
People from Rhineland-Palatinate
Bread is a type of baked food.
It is mainly made from dough, which is made mainly from flour and water.
Usually, salt and yeast are added.
Bread is often baked in an oven.
It can be bought all over the world.
Bread can be toasted or used to make sandwiches.
Pizza is a food-based on bread.
There are many different kinds of bread.
Leavened bread is made by adding yeast or other leavening agents to the dough.
The yeast produces gas that makes the dough lighter.
Leavened bread can be made into larger loaves baked in an oven.
This is the main type of bread eaten in Europe, America, and many parts of Asia.
Unleavened flatbread is baked from a dough of water and flour, with no yeast.
It is baked in flat rounds like tortilla or chapati.
This type of bread cannot be made thick as it would be too dense to eat.
Unleavened bread is eaten throughout Greece, Africa, parts of Asia, and as the Central America such as Pitta bread or tortilla.
Baking can be done on a metal plate or hot stone, or in an oven.
The color and taste of the bread depending on the kind of flour used and the style of baking.
Flour made from the whole grain gives darker bread.
Flour made just from the polished wheat grain gives a very white bread.
Rye and barley flour give darker types of bread.
The type of flour also changes how long the bread can be kept before going bad.
Some strains of wheat are resistant to fungus, but may not produce bread as tasty as a weaker strain.
Religious breads
Christianity and Judaism have rules about the use of bread in their religions.
Unleavened bread (matzo) is eaten by Jews during the Passover.
The Catholic celebration of the Eucharist uses unleavened wafers.
Orthodox churches forbid the use of unleavened bread for the Eucharist (Old Testament) and permit leavened bread only as a symbol of the New.
This was one of the three points of contention that brought about the schism between Eastern and Western churches in 1054.
Types of bread
Injera
Khachapuri
Markouk in Egypt and the Levant
Matzo in all Kosher communities
North American biscuit
Rice bread
Rye bread (Includes Pumpernickel)
Sprouted bread
White Bread
Wholemeal bread
Bread is an important part of life in many countries because so many people eat it.
In many cultures, bread is so important that it is part of religious rituals.
Cake is made in a similar way to bread but sugar, fat, and milk are added to the dough and often more ingredients.
Shinto () is a form of Japanese animism.
It has many kami, translated as gods or nature spirits.
Some "kami" are just spirits of certain places, and some are the overall "kami" (like "Amaterasu", the Sun goddess).
The word "Shinto" comes from the Japanese words "", shin—the word for spirit or god, and "", tō—the word for "the way" or "path".
So, Shinto means "the way of the gods."
State Shinto was the main religion of Japan before World War II.
During the period 1868 to 1945 the Japanese government used Shinto for propaganda.
All Japanese were forced to register with their local shrine.
All Shinto priests worked for the government.
War was seen as a sacred duty.
The Emperor of Japan was seen as a god.
Japanese Buddhism was also involved with the war effort (See Zen at War).
Shinto has many rituals and customs, and some are done every day.
Festivals are frequent.
Some people mix Shinto and Buddhist rituals and beliefs.
Although Jinja-Honcho manages almost all shrines, some, such as Yasukuni, are run separately.
Amaterasu, the Sun Goddess, is seen as the holiest of all Shinto kami.
Her shrine is in Ise, Japan.
Kokugakuin University Encylopedia of Shinto
A volcano is a mountain that has lava (hot, liquid rock) coming out from a magma chamber under the ground, or did have in the past.
Volcanoes are formed by the movement of tectonic plates.
The Earth's crust has 17 major, rigid tectonic plates.
These float on a hotter, softer layer in its mantle.
Volcanoes are often found where tectonic plates are moving apart or coming together.
Volcanoes can also form where there is stretching and thinning of the crust's plates, e.g., in the East African Rift.
Volcanoes are usually not found where two tectonic plates slide past one another.
Volcanism away from plate boundaries is caused by mantle plumes.
These so-called "hotspots", for example Hawaii, are thought to arise from upwelling magma from the core–mantle boundary, 3,000 km deep in the Earth.
Most volcanoes have a volcanic crater at the top.
When a volcano is active, materials come out of it.
The materials include lava, steam, gaseous sulfur compounds, ash and broken rock pieces.
When there is enough pressure, the volcano erupts.
Some volcanic eruptions blow off the top of the volcano.
Sometimes, the magma comes out quickly and sometimes it comes slowly.
Some eruptions come out at a side instead of the top.
Volcanoes are found on planets other than Earth.
An example is Olympus Mons on Mars.
Mauna Loa is 4,196 meters tall.
The largest recent eruption from Mauna Loa left a lava trail  long.
Types of volcanoes
The lava and pyroclastic material (clouds of ash, lava fragments and vapor) that comes out from volcanoes can make many different kinds of land shapes.
There are two basic kinds of volcanoes.
Shield volcanoes
Shield volcanoes are built out of layers of lava from continual eruptions (without explosions).
Because the lava is so fluid, it spreads out, often over a wide area.
Shield volcanoes do not grow to a great height, and the layers of lava spread out to give the volcano gently sloping sides.
Shield volcanoes can produce huge areas of basalt, which is usually what lava is when cooled.
The base of the volcano increases in size over successive eruptions where solidified lava spreads out and accumulates.
Some of the world's largest volcanoes are shield volcanoes.
Even though their sides are not very steep, shield volcanoes can be huge.
Mauna Kea in Hawaii is the biggest mountain on Earth if it is measured from its base on the floor of the sea.
Stratovolcanoes
A stratovolcano, also known as a composite volcano, is a tall, conical volcano.
It is built up of many layers of hardened lava, tephra, pumice, and volcanic ash.
Unlike shield volcanoes, stratovolcanoes have a steep profile and periodic eruptions.
The lava that flows from stratovolcanoes cools and hardens before spreading far.
It is sticky, that is, it has high viscosity.
The magma forming this lava is often felsic, with high-to-intermediate levels of silica, and less mafic magma.
Big felsic lava flows are uncommon, but have travelled as far as .
Two famous stratovolcanoes are Japan's Mount Fuji, and Vesuvius.
Both have big bases and steep sides that get steeper and steeper as it goes near the top.
Vesuvius is famous for its destruction of the towns Pompeii and Herculaneum in 79 AD, killing thousands.
A caldera is a basin-like feature formed by collapse of land after a volcanic eruption.
This happens after a huge stratovolcano blows its top off.
The base of the crater then sinks, leaving a caldera where the top of the volcano was before.
Krakatoa, best known for its catastrophic eruption in 1883, is much smaller now.
How volcanoes are formed
Volcanoes are made when two tectonic plates come together.
When these two plates meet, one of them (usually the oceanic plate) goes under the continental plate.
This is the process of subduction.
Afterwards, it melts and makes magma (inside the magma chamber), and the pressure builds up until the magma bursts through the Earth's crust.
The second way is when a tectonic plate moves over a hot spot in the Earth's crust.
The hot spot works its way through the crust until it breaks through.
The caldera of Yellowstone Park was formed in that way; so were the Hawaiian Islands.
A traditional way to classify or identify volcanoes is by its pattern of eruptions.
Those volcanoes which may erupt again at any time are called active.
Those that are now quiet called dormant (inactive).
Those volcanoes which have not erupted in historical times are called extinct.
An active volcano is currently erupting, or it has erupted in the last 10,000 years.
An example of an active volcano is Mount St. Helens in the United States (US).
Dormant(inactive)
A dormant volcano is "sleeping," but it could awaken in the future.
Mount Rainier in the United States is considered dormant.
Extinct (dead volcano)
An extinct volcano has not erupted in the past 10,000 years.
Edinburgh Castle in Scotland sits on top of an extinct volcano.
Some volcanoes
Largest volcano on Earth
The Earth's largest volcano has been discovered.
It is 2 km below the sea on an underwater plateau known as the Shatsky Rise.
This is about 1,600 km east of Japan.
The previous record-holder, Mauna Loa in Hawaii, is still the largest volcano on land.
The 310,000 km2 (119,000 sq mi) volcano, Tamu Massif, is comparable in size to Mars' vast Olympus Mons volcano, which is the largest in the Solar System.
It was formed about 145 million years ago when massive lava flows erupted from the centre of the volcano to form a broad, shield-like feature.
That suggests the volcano produced a flood basalt eruption.
The Tamu Massif extends some 30 km (18 miles) into the Earth's crust.
The researchers doubted the submerged volcano's peak ever rose above sea level during its lifetime and say it is unlikely to erupt again.
"The bottom line is that we think that Tamu Massif was built in a short (geologically speaking) time of one to several million years and it has been extinct since," co-author William Sager, of the University of Houston told the AFP news agency.
"There were lots of oceanic plateaus (that) erupted during the Cretaceous period (145-65 million years ago) but we don't see them since.
Scientists would like to know why... The biggest oceanic plateau is Ontong Java plateau, near the equator in the Pacific, east of the Solomon Islands.
It is much bigger than Tamu  it's the size of France".
The United States Geological Service (USGS) Volcano page
Glossary of Volcanic Terms from USGS
Volcanic and Geologic Terms  from Volcano World  - University of North Dakota (UND)
Television program (BBC) on the prediction of Popocatepetl's 2000 eruption
The Big Bang is a scientific theory about how the universe started, and then made the stars and galaxies we see today.
The Big Bang is the name that scientists use for the most common theory of the universe, from the very early stages to the present day.
The universe began as a very hot, small, and dense superforce (the mix of the four fundamental forces), with no stars, atoms, form, or structure (called a "singularity").
Then about 13.8 billion years ago, space expanded very quickly (thus the name "Big Bang").
This started the formation of atoms, which eventually led to the formation of stars and galaxies.
It was Georges  who first noted (in 1927) that an expanding universe could be traced back in time to an originating single point.
The universe is still expanding today, and getting colder as well.
As a whole, the universe is growing and the temperature is falling as time passes.
Cosmology is the study of how the universe began and its development.
Some scientists who study cosmology have agreed that the Big Bang theory matches what they have observed so far.
Fred Hoyle called the theory the "Big Bang" on his radio show.
He did not believe the Big Bang was correct.
Scientists who did not agree with him thought the name was funny and decided to use it.
Scientists base the Big Bang theory on many different observations.
The most important is the redshift of very far away galaxies.
Redshift is the Doppler effect occurring in light.
When an object moves away from Earth, its color rays look more similar to the color red than they actually are, because the movement stretches the wavelength of light given off by the object.
Scientists use the word "red hot" to describe this stretched light wave because red is the longest wavelength on the visible spectrum.
The more redshift there is, the faster the object is moving away.
By measuring the redshift, scientists proved that the universe is expanding, and they can work out how fast the object is moving away from the Earth.
With very exact observation and measurements, scientists believe that the universe was a singularity approximately 13.8 billion years ago.
Because most things become colder as they expand, scientists assume that the universe was very small and very hot when it started.
Other observations that support the Big Bang theory are the amounts of chemical elements in the universe.
Amounts of very light elements, such as hydrogen, helium, and lithium seem to agree with the theory of the Big Bang.
Scientists also have found "cosmic microwaves background radiation".
This radiation is known as radio waves, and they are everywhere in the universe.
This radiation is now very weak and cold, but a long time ago it was very strong and very hot.
It can be said that time had no meaning before the Big Bang.
If the Big Bang was the beginning of time, then there was no universe before the Big Bang, since there could not be any "before" if there was no time!
Other ideas state that the Big Bang was not the beginning of time 13.8 billion years ago.
Instead, some believe that there was a completely different universe before the Big Bang, and it may have been very different from the one we know today.
Nonetheless, in November 2019, Jim Peebles, awarded the 2019 Nobel Prize in Physics for his theoretical discoveries in physical cosmology.
Noted, in his award presentation, that he does not support the Big Bang Theory, due to the lack of concrete supporting evidence, and stated, "It's very unfortunate that one thinks of the beginning whereas in fact, we have no good theory of such a thing as the beginning."
Graphical timeline of the universe
Gmail is a free e-mail service that is run by Google.
It can be accessed on the web, by POP3, or by IMAP.
Some of the competitors to Gmail are Yahoo!
Mail, Hotmail/Windows Live Mail, and Inbox.
The space given to any Gmail member is increased a small amount every second, and as of July 26, 2012, Google provides each account with about 10272 MB of space.
Google Apps is a service from Google that was created in February 2006 as Gmail for your domain.
It is to allow system administrators of a company or organisation to create email accounts for their own domain.
Trademark issues
In the United Kingdom (UK), the trademark "Gmail" was owned by another company before Gmail by Google was started.
Thus, the United Kingdom uses a domain of "googlemail.com" for their users, and the logo has the words of "Google Mail" instead of the normal "Gmail".
Gmail Website
An astronomer is a scientist who studies astronomy.
Observational astronomers work in observatories with telescopes to collect information from things in outer space such as planets, stars, or galaxies.
Theoretical astronomers study the collected information, and use it to help us understand how the universe behaves.
List of Astronomers
Analysis is the process of breaking a complex topic or substance into smaller parts to gain a better understanding of it.
The technique has been applied in the study of mathematics and logic since before Aristotle (384–322 B.C.), though analysis as a formal concept is a relatively recent development.
The word comes from the Ancient Greek ἀνάλυσις (analusis, "a breaking up", from ana- "up, throughout" and lysis "a loosening").
Mathematical analysis is the name given to any branch of mathematics that looks at what functions are, how they behave, and what things can be done with them.
Analytical chemistry looks at the qualities of substances, and their composition.
The process of breaking up a concept, proposition, or fact into its simple or ultimate constituents.
Cambridge Dictionary of Philosophy.
2nd ed, 1999, ed.
Robert Audi.
Resolution into simpler elements by analysing.
2. (
Maths) Use of algebra and calculus in problem-solving.
Concise Oxford Dictionary.
1976, ed.
J.B. Sykes.
The isolation of what is more elementary from what is more complex by whatever method.
Dictionary of Philosophy and Psychology.
1925, ed.
James Mark Baldwin, Vol.
The original Greek sense [was] a ‘loosening up’ or ‘releasing’.
Geometry assumes a proposition to be true and searches for another known truth from which the proposition may be deduced.
Physical science resolves complex wholes into their elements.
A Kant Dictionary, 1995, by Howard Caygill.
The process of breaking a concept down into more simple parts, so that its logical structure is displayed.
Oxford Dictionary of Philosophy.
1996, Simon Blackburn
Philosophical analysis is a method of inquiry in which one seeks to assess complex systems of thought by ‘analysing’ them into simpler elements whose relationships are thereby brought into focus.
Routledge Encyclopedia of Philosophy.
1998, entry under ‘Conceptual Analysis’ by Robert Hanna
Research methods
Foolishness is when someone acts without wisdom or sense.
A foolish decision is one made without careful reasoning or judgement.
An act of foolishness is called folly.
A person who shows foolishness may be called a fool.
It is different to stupidity, which is the lack of intelligence.
A fool's errand is a useless piece of work.
A fool's paradise a happy state for which there is no good reason.
The wise fool is a common literary character, a person who appears at first to be unintelligent but then reveals him or herself to possess a grest deal of wisdom.
An example of this is Sancho Panza in Cervantes' Don Quixote.
Sancho is an uneducated peasant who at first seems to have little sense or experience.
However, as the tale unfolds, he reveals himself to possess a wealth of common sense, first expressed through endless proverbs, but then through his own skill.
In this sense he provides a comic juxtaposition to Quixote himself, who is highly educated but insane; both of them supply what the other lacks.
Aristotle (Stagira, Macedonia, 384 BC – Chalicis, Euboea, Greece, 7 March 322 BC) was a Greek philosopher.
He was one of the most important philosophers in the history of Western civilization.
Aristotle probably wrote many books, but very few of those books survive.
Aristotle tutored Alexander the Great when Alexander was a child.
Aristotle's father was named Nicomachus.
He was a soldier for King Amyntas of Macedonia.
At about the age of eighteen, Aristotle went to Athens to become a student of Plato at Plato's Academy.
Aristotle remained at the academy until he was 27.
He left after Plato died in 347 BC.
He then traveled with Xenocrates to Asia Minor.
While in Asia, Aristotle traveled with Theophrastus to the island of Lesbos.
They researched the botany and zoology of the island.
In 343 B.C., Philip II of Macedon invited Aristotle to tutor his son Alexander the Great.
Aristotle was put in charge of the royal academy of Macedon.
During that time, he did not only teach Alexander; he also taught two other future kings: Ptolemy and Cassander.
Aristotle encouraged Alexander to conquer lands to the east because he believed in ethnocentrism. (
Ethnocentrism is the belief that one's own culture is better than all of the other cultures.)
Aristotle believed Greek culture was better than all of the other cultures.
He encouraged Alexander to conquer Persia, which was an empire to the east, because he thought it would be better if the Greeks were in charge.
One time, he advised Alexander to be 'a leader to the Greeks and a despot to the barbarians, to look after the former as after friends and relatives, and to deal with the latter as with beasts or plants'.p58
By 335 BC Aristotle returned to Athens.
He started his own school there.
It was called the Lyceum.
Aristotle taught courses at the school for twelve years.
During this time (335 to 323 B.C.), Aristotle probably wrote many of his works.
Aristotle wrote many dialogues.
Only parts of his dialogues survive.
The works that have survived are torn and hard to read.
They were probably lecture notes for his students.
All of Aristotle's works are like an encyclopedia of everything that the Greeks knew.
Some people think Aristotle was probably the last person to know everything there was to know about in his own time.
Near the end of Alexander's life, he began to think people might be trying to kill him.
He threatened Aristotle in letters he wrote to him.
Aristotle often said that he disliked that Alexander called himself a god.
The king executed Aristotle's grandnephew Callisthenes as a traitor.
Alexander died in Babylon in 323 B.C. without ever going back to Greece.
When Alexander died, Athenians started to dislike Macedonians again and Aristotle left the city.
He died in Euboea of natural causes that same year, 322 BC.
The three greatest ancient Greek philosophers were Aristotle, Plato, and Socrates.
Socrates taught Plato, then Plato taught Aristotle.
These three thinkers turned early Greek philosophy into the beginnings of Western philosophy as it is today.
Plato's main ideas were that knowledge from the senses was always confused and not pure.
True knowledge can be gotten from the thinking soul that turns away from the world.
Only the soul can have knowledge of "Forms", the real way things are.
The world is only a copy of these "Forms" and is not perfect.
Aristotle thought differently.
He thought that knowledge from the senses was more important.
These thoughts became some of the roots of the scientific method after hundreds of years.
Most of the things Aristotle wrote that we still have today are notes from his speaking and teaching.
Some of his important writings are Physics, Metaphysics, (Nicomachean) Ethics, Politics, De Anima (On the Soul), and Poetics.
He also had problems with the atomic theory.
He did not believe in Democritus' theories about the atomic theory.
He believed that all matter was continuous whereas Democritus stated the all matter was made up of tiny indivisible things called "atoms".
Democritus was proved right by physicist John Dalton in 1804.
Aristotle created a form of logic.
His logic is called sentential logic because it uses sentences for the syllogism.
Aristotle's logic influenced the history of Western thought.
It was Aristotle's logic which was copied and used in the Arabic and Latin mediaeval traditions.
It was dominant for two and a half thousand years, until the late 19th century.
Then modern logic was started by Gottlob Frege, Charles Sanders Peirce and others.
Aristotle is the earliest natural historian whose work has survived in some detail.
He certainly did research on the natural history of Lesbos, and the surrounding seas and neighbouring areas.
The works History of Animals, Generation of Animals and Parts of Animals have observations and interpretations, along with some myths and mistakes.
The most striking passages are about the sea-life round Lesbos.
As well as live observation, he got specimens from the catches of fishermen.
His observations on catfish, electric fish (Torpedo) and angler-fish are detailed.
His writing on cephalopods such as Octopus, Sepia (cuttlefish) and the paper nautilus (Argonauta argo) are accurate.
His description of the hectocotyl arm, used in sexual reproduction, was widely disbelieved until its rediscovery in the 19th century.
He separated the aquatic mammals from fish, and knew that sharks and rays were part of the group he called Selachē (Selachimorpha).
Another good example of his methods comes from the Generation of Animals in which Aristotle describes breaking open fertilized chicken eggs at intervals to observe when visible organs were generated.
He gave accurate descriptions of ruminants' four-chambered fore-stomachs, and of the ovoviviparous egg development of the houndshark Mustelus mustelus.
Categories (terms)
On Interpretation (propositions, truth)
Prior Analytics (syllogistic logic)
Posterior Analytics (scientific method)
Topics (rules for argument and debate)
On Sophistical Refutations (fallacies)
Science and nature
Physics (change, motion, void, time)
On the Heavens (not the religious concept: refers to astronomy)
On Generation and Corruption (on the process of life)
Meteorology (origin of comets, weather, disasters)
The Parva Naturalia (psychological works)
Sense and sensibilia (faculties, senses, mind, imagination)
On Memory,
Sleep, Dreams, and Prophesy
Length of life
Works on natural history
History of Animals
On the parts of Animals
On the Movement of Animals
On the Progression of Animals
On the Generation of Animals
Philosophical works
Metaphysics (substance, cause, form, potentiality)
Nicomachean Ethics (soul, happiness, virtue, friendship)
Eudemian Ethics, virtues & vices
Politics (best states, utopias)
Rhetoric (debate)
Poetics (tragedy, epic poetry)
The Constitution of the Athenians
Influence of Aristotle's work
Aristotle is still one of the most influential people who ever lived.
He contributed to almost every kind of knowledge in his day, and he started many new fields.
"It is doubtful whether any human being has ever known as much as he did".
Despite these achievements, Aristotle's errors are thought by some, such as Peter Medawar, to have held back science considerably.
Bertrand Russell notes that "almost every serious intellectual advance has had to begin with an attack on some Aristotelian doctrine".
Russell also refers to Aristotle's Ethics as "repulsive", and calls his logic "as definitely antiquated as Ptolemaic astronomy".
Russell says these errors make it difficult to do historical justice to Aristotle, until one remembers what an advance he made on his predecessors.
The immediate influence of Aristotle's work was felt as the Lyceum grew into the Peripatetic school of philosophers.
Aristotle's influence over Alexander the Great is seen in the latter's bringing with him, on his expedition,  biologists and researchers.
Works by Aristotle
384 BC births
322 BC deaths
Ancient Greek writers
Carl Edward Sagan (November 9, 1934 - December 20, 1996) was an American astronomer.
He was very interested in what life on other planets would be like, which is known as SETI (search for extraterrestrial intelligence).
Sagan was a science communicator, which meant he taught people about science.
He felt like the general public was losing interest in science, so he wrote many books and appeared on television to make it popular again.
He mostly talked about planetary science and topics related to space.
One of his most famous works includes.
Cosmos: A Personal Voyage.
Cosmos was a television series about many different scientific topics, which Sagan co-wrote and narrated.
It made him very famous outside the world of science.
Education and work
Carl Sagan was born in Brooklyn, New York City.
Carl's family was Jewish.
His father, Samuel Sagan, was an immigrant from the Russian Empire.
Samuel was born in 1905 in a city called Kamianets-Podilskyi.
The Russian Empire no longer exists, so today Kamianets-Podilskyi is in Ukraine.
Samuel made clothes for a living.
Carl's mother, Rachel Molly Gruber, was a housewife.
Carl had a sister named Carol, who became a social worker.
Carl was named after his grandmother, Chaiya (Clara).
Sagan attended the University of Chicago earning two degrees in physics.
He followed with a doctorate in Astronomy in 1960 and taught at Harvard University until 1968, when he moved to Cornell University.
Sagan became a teacher and director at Cornell in 1971.
He helped many unmanned spacecraft to explore outer space.
He thought of the idea of putting a message on spacecraft which could be understood by any life from another planet that might find it.
The first message sent into space was a large gold-plated label on the space probe Pioneer 10.
He continued to make the messages better.
The last message he helped with was the Voyager Golden Record that was sent out with the Voyager space probes.
Scientific achievements
He was well known as a writer who warned of the dangers of nuclear winter.
He helped people learn about the atmosphere of Venus, seasonal changes on Mars, and Saturn's moon Titan.
He showed that the atmosphere of Venus is very hot and dense.
He also said that global warming was a growing, man-made danger like the natural development of Venus into a hot and dangerous planet with greenhouse gases.
He suggested that the seasonal changes on Mars were due to dust storms.
Sagan was among the first to guess that Titan and Jupiter's moon Europa might have oceans or lakes, which means that life could be there.
Europa's underground ocean was later confirmed by the spacecraft Galileo.
Sagan thought the search for life on other planets was a good idea.
He said scientists should listen with large radio telescopes for signals from other planets.
He thought sending probes to other planets was a good idea.
Sagan was editor Icarus (a magazine about space exploration) for 12 years.
He helped start the Planetary Society and was a member of the SETI Institute Board of Trustees.
Social concerns
Sagan also believed that the Drake equation suggested that many kinds of intelligent life could form, but that the lack of evidence (the Fermi paradox) suggests that intelligent beings destroy themselves rather quickly.
This made him keen to talk about ways that humanity could destroy itself, in the hope of avoiding such destruction.
Under the name "Mr. X," Sagan wrote about pot smoking in the 1971 book Reconsidering Marijuana.
Lester Grinspoon (the book's editor), told this to Keay Davidson, Sagan's biographer.
Sagan said that marijuana helped him write some of his books.
Sagan was very good at helping people to understand the cosmos.
He gave the 1977/1978 Christmas Lectures for Young People at the Royal Institution.
He wrote (with Ann Druyan, who became his third wife) and made the very popular thirteen-part PBS television series Cosmos; he also wrote books to help science become more popular (The Dragons of Eden, which won a Pulitzer Prize, Broca's Brain, etc.)
and a novel, Contact, that was a best-seller and was made into a film starring Jodie Foster in 1997.
The film won the 1998 Hugo Award.
After Cosmos, Sagan was linked with the catchphrase "billions and billions", which he never used in the television series (but he often used the word "billions").
He wrote Pale Blue Dot: A Vision of the Human Future in Space, which was chosen as a notable book of 1995 by The New York Times.
Not all scientists agreed with him.
Although they all liked the way he made science popular, some were afraid that people would think that his personal opinions might be confused with real science.
What he said about the Kuwait oil well fires during the first Gulf War were shown later to be wrong.
Later in his life, Sagan's books showed his skeptical, naturalistic view of the world.
In his book The Demon-Haunted World, Sagan gave a list of mistakes he had made as an example of how science is self-correcting.
The compilation Billions and Billions: Thoughts on Life and Death at the End of the Millennium, published after Sagan's death, contains essays written by Sagan, such as his views on abortion, and Ann Druyan's account of his death as a non-believer.
After a long and difficult fight with myelodysplasia, Sagan died of pneumonia at the age of 62, on December 20, 1996, at the Fred Hutchinson Cancer Research Center in Seattle, Washington.
Sagan was very important, because he made science popular, and changed the way science was organized, and because he defended humanism, and argued against seeing things from only one point of view.
The landing site of the unmanned Mars Pathfinder spacecraft was renamed the Carl Sagan Memorial Station in honor of Dr. Sagan on July 5, 1997.
Asteroid 2709 Sagan is also named in his honor.
The 1997 movie Contact (see above), based on Sagan's novel of the same name, and finished after his death, ends with the dedication "For Carl."
Awards and medals
Apollo Achievement Award - National Aeronautics and Space Administration
Chicken Little Honorable Mention - 1991 - National Anxiety Center
Distinguished Public Service - National Aeronautics and Space Administration
Emmy - Outstanding individual achievement - 1981 - PBS series Cosmos
Emmy - Outstanding Informational Series - 1981 - PBS series Cosmos
Exceptional Scientific Achievement Medal - National Aeronautics and Space Administration
Helen Caldicott Leadership Award - Women's Action for Nuclear Disarmament
Homer Award - 1997 - Contact
Hugo Award - 1998 - Contact
Hugo Award - 1981 - Cosmos
Hugo Award - 1997 - The Demon-Haunted World
In Praise of Reason Award - 1987 - Committee for the Scientific Investigation of Claims of the Paranormal
Isaac Asimov Award - 1994 - Committee for the Scientific Investigation of Claims of the Paranormal
John F. Kennedy Astronautics Award - American Astronautical Society
John W. Campbell Memorial Award - 1974 - The Cosmic Connection
Konstantin Tsiolkovsky Medal - Soviet Cosmonauts Federation
Locus Poll Award 1986 - Contact
Lowell Thomas Award - Explorers Club - 75th Anniversary
Masursky Award - American Astronomical Society
Peabody - 1980 - PBS series Cosmos
Public Welfare Medal - 1994 - National Academy of Sciences
Pulitzer Prize for Literature - 1978 - The Dragons of Eden
SF Chronicle Award - 1998 - Contact
Carl Sagan Memorial Award - Named in his honor
Related books and media
Sagan, Carl and Jonathon Norton Leonard and editors of Life, Planets.
Time, Inc., 1966
Sagan, Carl and I.S. Shklovskii, Intelligent Life in the Universe.
Random House, 1966
Sagan, Carl, Communicaton with Extraterrestrial Intelligence.
MIT Press, 1973
Sagan, Carl, et al.
Mars and the Mind of Man.
Harper & Row, 1973
Sagan, Carl, Other Worlds.
Bantam Books, 1975
Murmurs of Earth: The Voyager Interstellar Record.
Random House, 1977
Sagan, Carl et al.
The Nuclear Winter: The World After Nuclear War.
Sidgwick & Jackson, 1985
Sagan, Carl and James Randi, The Faith Healers.
Prometheus Books, May 1989, , 318 pgs
Sagan, Carl and Richard Turco, A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race.
Random House, 1990
Sagan, Carl, The Dragons of Eden: Speculations on the Evolution of Human Intelligence.
Ballantine Books, December 1989, , 288 pgs
Sagan, Carl, Broca's Brain: Reflections on the Romance of Science.
Ballantine Books, October 1993, , 416 pgs
Sagan, Carl and Ann Druyan, Shadows of Forgotten Ancestors: A Search for Who We Are.
Ballantine Books, October 1993, , 528 pgs
Sagan, Carl and Ann Druyan, Comet.
Ballantine Books, February 1997, , 496 pgs
Sagan, Carl, Contact.
Doubleday Books, August 1997, , 352 pgs
Sagan, Carl, Pale Blue Dot: A Vision of the Human Future in Space.
Ballantine Books, September 1997, , 384 pgs
Sagan, Carl and Ann Druyan, Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium.
Ballantine Books, June 1998, , 320 pgs
Sagan, Carl, The Demon-Haunted World: Science As a Candle in the Dark.
Ballantine Books, March 1997, , 480 pgs
Sagan, Carl and Jerome Agel, Cosmic Connection: An Extraterrestrial Perspective.
Cambridge University Press, January 15, 2000, , 301 pgs
Sagan, Carl, Cosmos.
Random House, May 7, 2002, , 384 pgs
Zemeckis, Robert, Contact.
Warner Studios, 1997, ASIN 0790736330 IMDB
Davidson, Keay, Carl Sagan: A Life.
John Wiley & Sons, August 31, 2000, , 560 pgs
In Memory of Carl Sagan.
Tributes by Tom McDonough, James Randi and Michael Shermer, and a selection of quotes from Sagan's works, published in Skeptic, Vol.
4, 1996, pp.
CarlSagan.
Homepage of Cosmos Studios, which sells the Cosmos series on DVD and VHS video tape.
Carl Sagan, Cornell astronomer, dies today (Dec. 20) in Seattle.
Cornell University press release on Sagan's death.
Even in Death, Carl Sagan's Influence Is Still Cosmic by William J. Broad, The New York Times, November 30, 1998.
Describes Sagan's legacy for space science.
Astronomy Picture of the Day: Carl Sagan.
December 26, 1996.
Contact: A Eulogy to Carl Sagan, by Dr. Ray Bohlin, president of Probe Ministries.
Dr. Bohlin suggests that the movie Contact can serve as a fitting eulogy for Carl Sagan.
Sagan's scientific approach to the question, "was the universe created?"
is critically analyzed by Bohlin from his Christian perspective.
1934 births
1996 deaths
Agnostics
American astronomers
Deaths from pneumonia
Infectious disease deaths in the United States
Jewish American writers
Pulitzer Prize winners
Scientists from New York
Writers from New York City
Emmy Award winners
Matsuo Munefusa, known as Matsuo Bashō (, 1644 - November 28, 1694) was a Japanese poet.
He is known as the greatest maker of haiku, a kind of poetry with 17 syllables.
The Japanese written language was difficult to master, but haiku was easy for him to write.
Matsuo's haikus included characteristics of nature and the four seasons.
The reader has to use their imagination to understand his poems.
According to Japanese custom, he is usually called Basho without his family name, and his signature as a poet does not include his house name.
He signed usually "はせを".
He is one of the greatest writers of the Edo period, and he raised the haiku form to its highest level.
He was born in Iga, now a part of Mie prefecture in a samurai (Japanese warrior) family.
After many years of samurai life he found that poetry would be his life work, and gave up being a samurai.
He started his life as a poet when he served his lord as a samurai.
Matsuo became educated in classical Japanese poems.
First he named himself Tosei (桃青) meaning "unripe peach in blue".
Basho took this name because he admired a Chinese poet, Li Po whose name means plum in white.
He quit samurai life 1666, and in 1675 he moved to Edo, today called Tokyo.
There, in 1678, he got to be a haiku master ("Sosho") and began the life of a working poet.
In 1680, he moved to Fukagawa, where he had a house.
This was just outside of Edo.
One of his followers gifted him a banana plant (basho-an).
He planted the plant and called himself Basho because it became his favorite tree in his garden.
In his life, Basho visited many places.
Those travels were important for his writings.
He visited his disciples (followers) and taught them by making renga, a series of haiku, with them.
He also visited famous places in Japanese history.
These visits made his writing much stronger.
His most famous book is Oku no Hosomichi ("The Narrow Road Through the Deep North").
This book was written after a trip.
On the trip, Basho and his disciple left Edo on March 24, 1689.