Isocolon

Isocolon is a rhetorical scheme in which parallel elements possess the same number of words or syllables. As in any form of parallelism, the pairs or series must enumerate like things to achieve symmetry. The scheme is called bicolon, tricolon, or tetracolon depending on whether they are two, three, or four parallel elements.

Etymology
The term, a compound of ἴσος ísos 'equal' and κῶλον kôlon 'member, clause' was used in the classical Greek rhetorical literature:

The Greek plural is 'isocola', but 'isocolons' is also used in English.

Bicolon
An example of bicolon is the advertising slogan "buy one, get one free" (you pay for one item but you get another free).

In Biblical poetry it is standard to see a pair of adjacent lines of poetry in which the second echoes the meaning of the first. This can be considered a bicolon. For example:
 * 1) When Israel went out of Egypt, * the house of Jacob from a barbarous people:
 * 2) Judea made his sanctuary, * Israel his dominion.
 * 3) The sea saw and fled: * Jordan was turned back.
 * 4) The mountains skipped like rams, * and the hills like the lambs of the flock.
 * 5) What ailed thee, O thou sea, that thou didst flee: * and thou, O Jordan, that thou wast turned back?
 * 6) Ye mountains, that ye skipped like rams, * and ye hills, like lambs of the flock?
 * 7) At the presence of the Lord the earth was moved, * at the presence of the God of Jacob:
 * 8) Who turned the rock into pools of water, * and the stony hill into fountains of waters.
 * &mdash;Psalm 113:1-8 (Psalm 114 Hebrew)

Tricolon

 * Veni, vidi, vici
 * &mdash; (Julius Caesar)


 * "I came; I saw; I conquered."

A tricolon that comprises parts in increasing size, magnitude or intensity is called a tricolon crescens, or an ascending tricolon. Tricolon can sometimes be a hendiatris.

Similarly, tricolon that comprises parts that decrease in size, magnitude, intensity, or word length is called a tricolon diminuens, or a descending tricolon.

Abraham Lincoln used tricolon in many of his speeches. His Gettysburg Address has the following phrase: "We cannot dedicate – we cannot consecrate – we cannot hallow..." Lincoln wrote in his second inaugural address, "with malice toward none, with charity toward all, with firmness in the right...".

Winston Churchill used the tricolon frequently, as in his June 1941 speech regarding the German invasion of the Soviet Union, when he stated "It is a war in which the whole British Empire and Commonwealth of Nations is engaged without distinction of race, creed or party."

Repeating the same thing multiple times is a special case of an isocolon, as a way of saying that only one thing is important, and it is very important. In about 1500, when Louis XII asked Giangiacopo Trivulzio what was necessary to win the war against Ludovico Sforza, Trivulzio answered: "Three things, Sire, Money, money, money!" In the 20th century, the cliché "Location, location, location" was said to enumerate the three most important attributes of real property. This phrase appears in print in Chicago as early as 1926, but is nonetheless frequently credited, incorrectly, to the British real estate magnate Lord Harold Samuel. British Prime Minister Tony Blair set out his priorities for office in 1997 with "Education, education, education".

Tetracolon
Tetracola are sometimes called "quatrains" (cf. the usual meaning of quatrain).

An example of a tetracolon may be cited from a poem by Gabriele D'Annunzio: "Era calcina grossa, e poi era terra cotta, e poi pareva bronzo, e ora è cosa viva.

("It was raw mortar, and then it was terra cotta, and then it seemed like bronze, and now it is a living thing.")"

Another example can be cited from Richard II, by Shakespeare

"I’ll give my jewels for a set of beads, My gorgeous palace for a hermitage, My gay apparel for an almsman’s gown, My figured goblets for a dish of wood."

Special cases
A special type of collocation known as an irreversible binomial is a bicolon that is both short and so well known that it becomes a fixed expression. Not all irreversible binomials are bicolons or tricolons, however. Irreversible binomials generally consist of only a few words at most.

Examples of irreversible binomials that are bicolons or tricolons:
 * smoke and mirrors
 * alive and kicking
 * cloak and dagger
 * command and control
 * each and every
 * part and parcel
 * lie, cheat, or steal
 * name it and claim it
 * rank and file
 * signed, sealed, and delivered
 * tic-tac-toe
 * finders, keepers; losers, weepers
 * carpe diem, carpe noctem, carpe vitam
 * in vino veritas, in aqua sanitas
 * brain and brawn
 * meat and potatoes
 * rape and pillage
 * divide and conquer
 * tall, dark, and handsome
 * pins and needles
 * brains and beauty
 * rock and roll
 * spick and span
 * chalk and cheese

Examples of irreversible binomials that are not bicolons or tricolons:
 * lost and found
 * between the devil and the deep blue sea
 * between a rock and a hard place
 * double trouble (a verb and noun)
 * high crimes and misdemeanors
 * over and done with
 * Skull and crossbones
 * sugar and spice and everything nice