The Age of Unreason is a series of four novels written by Gregory Keyes

Gregory Keyes

Gregory Keyes is an American writer of science fiction and fantasy who has written both original and media-related novels under both the names "J. Gregory Keyes" and "Greg Keyes". He is famous for his quartet The Age of Unreason, a steampunk/alchemical story starring Benjamin Franklin and Isaac...

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• Newton's Cannon
  Newton's Cannon
  Newton's Cannon is the first novel in Gregory Keyes's The Age of Unreason series. The main protagonist for the novel is Benjamin Franklin, other key characters to the novel are James Franklin - Ben's brother, John Collins - Ben's friend, as well as Adrienne and King Louis XIV - the Sun King.-The...
  
  (1998), ISBN 1-56865-829-X
• A Calculus of Angels
  A Calculus of Angels
  A Calculus of Angels is the second book in Gregory Keyes' The Age of Unreason series. It was initially published by Del Rey on March 30, 1999...
  
  (1999), ISBN 0-7394-0260-9
• Empire of Unreason (2000), ISBN 0-345-40609-5
• The Shadows of God (2001), ISBN 0-345-43904-X

Its title is a reference to Thomas Paine

Thomas Paine

Thomas "Tom" Paine was an English author, pamphleteer, radical, inventor, intellectual, revolutionary, and one of the Founding Fathers of the United States...

's treatise The Age of Reason

The Age of Reason

The Age of Reason; Being an Investigation of True and Fabulous Theology is a deistic pamphlet, written by eighteenth-century British radical and American revolutionary Thomas Paine, that criticizes institutionalized religion and challenges the legitimacy of the Bible, the central sacred text of...

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The story spans the late seventeenth and early eighteenth century, with the action moving between England and France, later involving Russia, Austria, the Republic of Venice

Republic of Venice

The Republic of Venice or Venetian Republic was a state originating from the city of Venice in Northeastern Italy. It existed for over a millennium, from the late 7th century until 1797. It was formally known as the Most Serene Republic of Venice and is often referred to as La Serenissima, in...

, and North America. The author makes use of pseudosciences (scientific alchemy

Alchemy

Alchemy is an influential philosophical tradition whose early practitioners’ claims to profound powers were known from antiquity. The defining objectives of alchemy are varied; these include the creation of the fabled philosopher's stone possessing powers including the capability of turning base...

 instead of our physics) that were popular at the time: using affinity and aether

Aether

-Metaphysics and mythology:* Aether , the material that fills the region of the universe above the terrestrial sphere* Aether was the personification of the "upper sky", space and heaven, in Greek mythology-Science and engineering:...

, for example. Some historical characters appear in important roles: Isaac Newton

Isaac Newton

Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...

, Voltaire

Voltaire

François-Marie Arouet , better known by the pen name Voltaire , was a French Enlightenment writer, historian and philosopher famous for his wit and for his advocacy of civil liberties, including freedom of religion, free trade and separation of church and state...

, Benjamin Franklin

Benjamin Franklin

Dr. Benjamin Franklin was one of the Founding Fathers of the United States. A noted polymath, Franklin was a leading author, printer, political theorist, politician, postmaster, scientist, musician, inventor, satirist, civic activist, statesman, and diplomat...

, Cotton Mather

Cotton Mather

Cotton Mather, FRS was a socially and politically influential New England Puritan minister, prolific author and pamphleteer; he is often remembered for his role in the Salem witch trials...

, King Louis XIV of France

Louis XIV of France

Louis XIV , known as Louis the Great or the Sun King , was a Bourbon monarch who ruled as King of France and Navarre. His reign, from 1643 to his death in 1715, began at the age of four and lasted seventy-two years, three months, and eighteen days...

, Emperor Peter the Great of Russia

Peter I of Russia

Peter the Great, Peter I or Pyotr Alexeyevich Romanov Dates indicated by the letters "O.S." are Old Style. All other dates in this article are New Style. ruled the Tsardom of Russia and later the Russian Empire from until his death, jointly ruling before 1696 with his half-brother, Ivan V...

, King Charles XII of Sweden, and Edward Teach, better known as the pirate Blackbeard

Blackbeard

Edward Teach , better known as Blackbeard, was a notorious English pirate who operated around the West Indies and the eastern coast of the American colonies....

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