The 2001 NFL season was the 82nd regular season of the National Football League. In the wake of the September 11 attacks, the NFL's week 2 games were postponed and rescheduled to the weekend of January 6 and January 7. In order to retain the full playoff format, all playoff games, including Super Bowl XXXVI, were rescheduled one week later; the New England Patriots won the Super Bowl, defeating the St. Louis Rams 20–17 at the Louisiana Superdome. Following a pattern set in 1999, the first week of the season was permanently moved to the weekend following Labor Day. With Super Bowls XXXVI-XXXVII scheduled for fixed dates, the league decided to eliminate the Super Bowl bye weeks for 2001 and 2002 to adjust. In the wake of the September 11 attacks, the games scheduled for September 16 and 17 were postponed and rescheduled to the weekend of January 6 and 7. In order to retain the full playoff format, all playoff games, including the Super Bowl, were rescheduled one week later; the season-ending Pro Bowl was moved to one week later.

This was the last season in which each conference had three divisions, as the conferences would be realigned to four divisions for the 2002 NFL season. Canceling the games scheduled for September 16 and 17 was considered and rejected since it would have canceled a home game for about half the teams, it would have resulted in an unequal number of games played: September 16 and 17 was to have been a bye for the San Diego Chargers, so that team would still have played 16 games that season and each of the other teams would have played only 15 games. As a result of rescheduling Week 2 as Week 17, the Pittsburgh Steelers ended up not playing a home game for the entire month of September; the ESPN Sunday Night Football game for that week was changed. It was scheduled to be Cleveland at Pittsburgh, but it was replaced with Philadelphia at Tampa Bay, seen as a more interesting matchup; the Eagles and Buccaneers would both rest their starters that night, would meet one week in the playoffs. In recognition of this, when NBC began airing Sunday Night Football in 2006, there would be no game scheduled for Weeks 11 to 17 – a game scheduled in the afternoon would be moved to the primetime slot, without stripping any teams of a primetime appearance.

This way of “flexible scheduling” would not be utilized at all in 2007, since 2008, it is only utilized in the final week. The games that made up Week 17 marked the latest regular season games to be played during what is traditionally defined as the "NFL season". Another scheduling change took place in October, when the Dallas Cowboys at Oakland Raiders game was moved from October 21 to 7 to accommodate a possible Oakland Athletics home playoff game on the October 21; the rescheduling ended up being unnecessary as the Athletics would not make it past the Division Series round. This was the only NFL season where every jersey had a patch to remember those who died on 9/11, while the New York Jets and New York Giants wore a patch to remember the firefighters who died; the season ended with Super Bowl XXXVI. Fumble recoveries will be awarded at the spot of the recovery, not where the player’s momentum carries him; this change was passed in response to two regular season games in 2000, Atlanta Falcons–Carolina Panthers and Oakland Raiders–Seattle Seahawks, in which a safety was awarded when a defensive player’s momentum in recovering a fumble carried him into his own end zone.

Taunting rules and roughing the passer will be enforced. Mike Pereira became the league's Director of Officiating, succeeding Jerry Seeman, who had served the role since 1991. Bill Leavy and Terry McAulay were promoted to referee. Phil Luckett returned to back judge, while another officiating crew was added in 2001 in preparation for the Houston Texans expansion team, the league's 32nd franchise, in 2002. Due to labor dispute, the regular NFL officials were locked out prior to the final week of the preseason. Replacement officials who had worked in college football or the Arena Football League officiated NFL games during the last preseason week and the first week of the regular season. A deal was reached before play resumed after the September 11 attacks. New Orleans Saints – Replaced their gold pants with black pants. Pittsburgh Steelers – New stadium: Heinz Field. San Diego Chargers – White pants with road uniforms. Denver Broncos – New stadium: Invesco Field. St. Louis Rams – New font for uniform numbers.

Philadelphia Eagles – New hard turf field, due to a cancelled preseason game scheduled against the Baltimore Ravens in which Ravens’ coach Brian Billick told officials of the NFL that he refused to have his team play on a slippery and bouncy turf field which he deemed unsafe. Buffalo Bills – Gregg Williams.

In logic and philosophy, an argument is a series of statements, called the premises or premisses, intended to determine the degree of truth of another statement, the conclusion. The logical form of an argument in a natural language can be represented in a symbolic formal language, independently of natural language formally defined "arguments" can be made in math and computer science. Logic is the study of the forms of reasoning in arguments and the development of standards and criteria to evaluate arguments. Deductive arguments can be valid or sound: in a valid argument, premisses necessitate the conclusion if one or more of the premisses is false and the conclusion is false. Inductive arguments, by contrast, can have different degrees of logical strength: the stronger or more cogent the argument, the greater the probability that the conclusion is true, the weaker the argument, the lesser that probability; the standards for evaluating non-deductive arguments may rest on different or additional criteria than truth—for example, the persuasiveness of so-called "indispensability claims" in transcendental arguments, the quality of hypotheses in retroduction, or the disclosure of new possibilities for thinking and acting.

The Latin root arguere is from Proto-Indo-European argu-yo-, suffixed form of arg-. Informal arguments as studied in informal logic, are presented in ordinary language and are intended for everyday discourse. Conversely, formal arguments are expressed in a formal language. Informal logic may be said to emphasize the study of argumentation, whereas formal logic emphasizes implication and inference. Informal arguments are sometimes implicit; that is, the rational structure – the relationship of claims, warrants, relations of implication, conclusion – is not always spelled out and visible and must sometimes be made explicit by analysis. There are several kinds of arguments in logic, the best-known of which are "deductive" and "inductive." An argument has more premises but only one conclusion. Each premise and the conclusion are truth bearers or "truth-candidates", each capable of being either true or false; these truth values bear on the terminology used with arguments. A deductive argument asserts that the truth of the conclusion is a logical consequence of the premises.

Based on the premises, the conclusion follows necessarily. For example, given premises that A=B and B=C the conclusion follows that A=C. Deductive arguments are sometimes referred to as "truth-preserving" arguments. A deductive argument is said to be invalid. If one assumes the premises to be true, would the conclusion follow with certainty? If yes, the argument is valid. Otherwise, it is invalid. In determining validity, the structure of the argument is essential to the determination, not the actual truth values. For example, consider the argument that because bats can fly, all flying creatures are birds, therefore bats are birds. If we assume the premises are true, the conclusion follows and thus it is a valid argument. If a deductive argument is valid and its premises are all true it is referred to as sound. Otherwise, it is unsound, as in the "bats are birds" If all its premises are true its conclusion must be true. Therefore, it is impossible for the conclusion to be false if all the premises are true An inductive argument, on the other hand, asserts that the truth of the conclusion is supported to some degree of probability by the premises.

For example, given that the U. S. military budget is the largest in the world it is probable that it will remain so for the next 10 years. Arguments that involve predictions are inductive. An inductive argument is said to be weak. If the premises of an inductive argument are assumed true, is it probable the conclusion is true? If so, the argument is strong. Otherwise, it is weak. A strong argument is said to be cogent. Otherwise, the argument is uncogent; the military budget argument example above is a cogent argument. A deductive argument is one that, if valid, has a conclusion, entailed by its premises. In other words, the truth of the conclusion is a logical consequence of the premises—if the premises are true the conclusion must be true, it would be self-contradictory to assert the premises and deny the conclusion, because the negation of the conclusion is contradictory to the truth of the premises. Deductive arguments may be either invalid. If an argument is valid, it is a valid deduction, if its premises are true, the conclusion must be true: a valid argument cannot have true premises and a false conclusion.

An argument is formally valid if and only if the denial of the conclusion is incompatible with accepting all the premises. The validity of an argument depends, not on the actual truth or falsity of its premises and conclusion, but on whether or not the argument has a valid logical form; the validity of an argument is not a guarantee of the truth of its conclusion. Under a given interpretation, a valid argument may have false premises that render it inconclusive: the conclusion of a valid argument with one or more false premises may be either true or false. Logic seeks to discover the forms that make arguments valid. A form of argument is valid i

Lisowczycy – the name of an early 17th-century irregular unit of the Polish-Lithuanian light cavalry. The Lisowczycy took part in many battles across Europe and the historical accounts of the period characterized them as agile and bloodthirsty, their numbers varied from a few hundreds to several thousands. The origin of the group can be traced to konfederacja, organized around 1604 by Aleksander Józef Lisowski, they began to grow in strength and fame a few years when Lisowski's irregulars were incorporated into the forces fighting in Muscovy. The Lisowczycy unit of the Polish cavalry received no formal wages, they relied on their speed and fought without tabors, foraging supplies from lands they moved through. The Lisowczycy were feared and despised by civilians wherever they passed and they gained dubious fame for the scores of atrocities they carried out. However, they were grudgingly respected by their opponents for their military skills, they did not hesitate to plunder their homeland, where they sacked the Racovian Academy university of the Polish brethren.

Such actions were among the reasons the Commonwealth ruler Sigismund III Vasa tried to keep them away from the Commonwealth for as long as possible. The Lisowczycy took part in many conflicts, including the Dymitriads and in the Battle of White Mountain, they were disbanded in 1635. An account of Lisowczycy's exploits was written by their chaplain, Wojciech Dembołęcki, in Przewagi Elearów polskich co ich niegdy Lisowczykami zwano. In 1604, during the early stages of the Polish–Swedish War, the Sejm of the Commonwealth failed to gather the money to pay its soldiers fighting in Livonia against the Swedes. Aleksander Józef Lisowski became one of the leaders of the resulting konfederacja – a section of the army that mutinied and decided to gather its outstanding wages by pillaging local civilians, not caring whether these owed their allegiance to the Commonwealth or to Sweden. Although this annoyed Great Hetman of Lithuania Jan Karol Chodkiewicz, resulted in Lisowski being banished from the Commonwealth, little was done to stop the mutineers.

Soon after, Lisowski with his followers joined the Sandomierz rebellion or rokosz of Zebrzydowski, a revolt against the absolutist tendencies of the King Sigismund III Vasa. After the rebel forces were defeated at the Battle of Guzow, Lisowski's fortunes turned for the worse and he became persona non grata in most of the Commonwealth, was forced to seek refuge with the powerful Radziwiłł family. In the meantime, Muscovy's Time of Troubles were brewing, Lisowski did not pass over the opportunity of profiting from this, as many other local magnates and noblemen had, by meddling in Russian affairs, he soon decided he could profit best by lending his support to the Muscovite pretender, False Dmitriy II. In 1608, together with Aleksander Kleczkowski, leading his forces – a band of few hundred ragtag soldiers of fortune Poles and Ruthenians – he defeated the armies of tsar Vasili Shuisky, led by Zakhary Lyapunov and Ivan Khovansky, near Zaraysk and captured Mikhailov and Kolomna, moving on to blockade Moscow.

However, he was soon to be defeated at Miedźwiedzi Bród. He reorganized the army and joined with Jan Piotr Sapieha, but they failed to capture the Troitse-Sergieva Lavra fortress and were forced to retreat to near Rakhmantsevo. Came successful pillages at Kostroma and some other cities, he clashed with Swedes operating in Muscovy during the Ingrian War. The Lisowczycy proved essential in the defence of Smolensk in 1612, when most of the Commonwealth regular army, the and joined the Rohatyn Confederation. For the next three years Lisowski's forces were of importance in the guarding of the Commonwealth border against Muscovy incursions. In 1615, Lisowski invaded Muscovy with 6 companies of cavalry, he besieged Bryansk and defeated the Muscovite relief force of a few thousand soldiers under Kniaz Yuri Shakhovskoy near Karachev. Lisowski moved on to defeat the Muscovite advance guard of a force under the command of Kniaz Dmitry Pozharsky, who decided to not to attack and fortified his forces inside a camp.

Lisowski's men broke contact with other forces, burned Belyov and Likhvin, took Peremyshl, turned north, defeated a Muscovite army at Rzhev, turned towards the Kara Sea coast to Kashin, burned Torzhok, returned to Commonwealth without any further contact with Muscovy forces. Until the autumn of 1616, Lisowski and his forces remained on the Commonwealth-Muscovy border, when Lisowski fell ill and died on October 11. In 1612, when the Polish occupation of the Moscow Kremlin had ended, loose Polish forces, which had fought under Lisowski, scattered over vast territory of the Tsardom of Russia, taking advantage of the so-called Time of Troubles. Exact whereabouts of Aleksander Jozef Lisowski at that time are unknown: the legendary leader most roam