"Not" or "not" in book title? [duplicate]

Assume I have written a book and want to name it:

The Joy of Not Being Stupid

Would the "not" be capitalized?

Blue book of grammar and punctuation: The following rules for capitalizing composition titles are universal.

•Capitalize the title's first and last word. •Capitalize verbs, including all forms of the verb to be (is, are, was, etc.). •Capitalize all pronouns, including it, he, who, that, etc.

•Capitalize the not.

Do not capitalize a, an, or the unless it is first or last in the title. •Do not capitalize the word and, or, or nor unless it is first or last in the title. •Do not capitalize the word to, with or without an infinitive, unless it is first or last in the title.

Capitalizing Words in Titles

From Basic Book Design- Wikibooks.

These rules are adapted from The Chicago Manual of Style.

1. The first and last words are always capitalized, even if fewer than five letters.

2. Words over five letters are always capitalized.

3. Verbs are always capitalized, even if fewer than five letters.

4. Nouns are always capitalized, even if fewer than five letters.

5. Unless the first or last words of a title, these are never capitalized: articles: a, an, the; conjunctions: and, but, or, nor; prepositions that are fewer than five letters long: at, by, for, from, in, into, of, off, on, onto, out, over (unless used as a verb), up, with; infinitives: to; "as" is never capitalized; o'Clock (since it means "of the clock")

6. These words are capitalized, even though they are fewer than five letters: also, be, if, than, that, thus, when.

   This explanation is not intended to be exhaustive. 
   

Another reference: The Major Words In The Titles Of Books, Articles, And Songs