Rule #1 Series or List
Use a colon to start a series/list that is introduced by an independent clause.
Friedrich Nietzsche wrote several of my favourite books: Thus Spoke Zarathustra, Beyond Good and Evil, and The Antichrist.
For many, Nietzsche is known for just two things: his atheism and his depression.
Rule #2 Consequence of an Action
Use a colon to introduce the effect or logical consequence of an action.
Looking at the world around him, Nietzsche finds that he can come to only one conclusion: God is dead.
Nietzsche wanted to demonstrate, through his radical language, that European society had finally made one social force irrelevant: Christianity.
Rule #3 Quotation
Use a colon before a long quotation that is an independent clause. In MLA Format, the quote should be four or more lines long.
Ever concerned with “will,” in Thus Spoke Zarathustra Nietzsche writes:
Will—that is the name of the liberator and joy-bringer; thus I taught you, my friends. But now learn this too: the will itself is still a prisoner. Willing liberates; but what is it that puts even the liberator himself in fetters? “It was”—that is the name of the will’s gnashing of teeth and most secret melancholy (139).
Rule #4 Letter or Memo
Use a colon after the salutation in a business letter or memo.
Dear Walter Kaufmann:
To the editorial board of The Journal of Nietzsche Studies:
Rule #5 Separating Chapter and Verse
Use a colon to separate the chapter and verse in religious scripture. Note that in MLA the correct punctuation for both religious scripture and plays is actually a period.
Thus Spoke Zarathustra works against Genesis 1:1, presenting self-creation in place of what we might call “God-creation.”
Fargard 2:1 of the Zend-Avesta (the primary holy text of Zoroastrianism, from which Nietzsche lifts the character “Zarathustra”) proves to be an important read for the involved Nietzsche scholar.
Rule #6 Separating Hours and Minutes
Use a colon to separate hours from minutes when stating the time.
I looked up at 2:30 in the morning and—shocked—put down my Ecce Homo, having finally realized that I really am a nerd.
Rule #7 Ratios
Use a colon to show a ratio.
“Understanding Nietzsche is a matter of proportion,” explained Dr. Smith. “It’s a 3:1 ratio. Three parts reading and rereading his texts as broadly as you can, one part reveling in the audacity of it all.”
For the philosophy quiz we were split up into teams of 12:1. That is, 12 undergrad students for every postgrad.