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Anthony’s NotesA personal field guide
From the notebook

Book Marking System

Handwritten source

The decision to formalize a reusable marking language appears on notebook p. 50 — Book Marking System (file not included in this release). This note is the expanded typed reference; Memory Retrieval Techniques covers what should happen after the marks are made.

The two books this system is built out of — both in the vault, neither previously linked here

This note describes how to mark. Those two describe why the marks are shaped this way and what happens to them after.

How to Read a Book - Mortimer J Adler Charles Van Doren — the source of the “mark according to function” principle. Adler’s four levels are the layer above this system:

  • Inspectional — orientation before detail; gives you a map so the deep read is cheaper.
  • Analytical — treat books as arguments, not authorities. This is the level the margin symbols below are actually serving.
  • Syntopical — comparing multiple works to build a synthesis. This is the level your vault is for, and the one marking alone can’t reach.

How to Take Smart Notes - Sönke Ahrens — what to do with the marks once the book is closed, and the strongest argument in the vault for why marking is not enough. Luhmann’s practice, per Ahrens:

  • Two separate boxes — a bibliographic one (references, brief notes on the literature) and a main one where ideas are generated.
  • He did not copy quotes. He made “a transition from one context to another … very much like a translation,” rewriting in full sentences in his own final-draft style.
  • Every new note was written while checking the existing box for connections — the link was made at write time, not later.
  • His claim about payoff: “the quality of a paper and the ease with which it is written depends more than anything on what you have done in writing before you even made a decision on the topic.”

The tension worth noticing: Ahrens would say the review marks below (the “what to do with it later” layer) are where most systems fail — deferring the translation step means it never happens. Adler would say marking is analytical reading. Your system currently sides with Adler; Ahrens is the objection to it.

Note: How to Take Smart Notes lives in 80 Blog & Writing/Books about Writing/ and was, before this line, the single most orphaned note in the vault — nothing linked to it at all, including the note you’re reading.

Below is a complete book-marking system designed for serious nonfiction reading, later review, and Obsidian note-making.

Core principle

Do not mark everything that sounds good. Mark according to function.

Every mark should answer one question:

“Why would I need to come back to this?”

Use three layers:

  1. Passage marks — what part of the page matters.
  2. Margin symbols — why it matters.
  3. Review marks — what to do with it later.

1. Basic Passage Marks

[

Bracket in the margin

Use for a full passage, paragraph, argument, or explanation.

Best for:

  • Main arguments
  • Historical explanations
  • Author’s reasoning
  • Important examples
  • Long claims that need context

Example:

[ This paragraph explains why the Enlightenment changed
  the basis of moral authority from revelation to reason.

Use brackets more than underlining.


Underline

Use only for exact wording.

Best for:

  • Definitions
  • Key phrases
  • Terms of art
  • Sentences you may quote
  • Memorable formulations

Example:

Underline: “absence of external impediments”

Do not underline whole paragraphs. That defeats the purpose.


Circle

Use for names, concepts, dates, schools, or technical terms.

Example:

Circle: Hobbes
Circle: natural law
Circle: 1648
Circle: compatibilism

This makes the page searchable by eye when reviewing.


Vertical line

|

Use beside a passage that is useful but not essential.

Think of this as a lighter version of a bracket.

Use for:

  • Helpful context
  • Secondary evidence
  • Supporting detail
  • Interesting but non-central points

2. Importance Marks

★

Major thesis

Use for one of the author’s central claims.

Example:

★ Christianity transformed the moral status of the weak and victimized.

Use sparingly. Maybe 1–5 per chapter.


★★

Book-level thesis

Use for a claim that seems central to the whole book.

Example:

★★ The modern concept of the individual emerged from Christian moral assumptions.

Use very rarely.


!

Important insight

Use when something strikes you as especially revealing, clarifying, or powerful.

Example:

! This explains why Nietzsche saw Christianity as a moral revolution.

!!

Extremely important

Use only when the passage changes your understanding of the subject.

Limit this heavily.


3. Argument Structure Marks

T

Thesis

The author’s main claim in a section or chapter.

Example:

T: Liberalism inherited moral assumptions from Christianity.

R

Reason

A reason the author gives in support of a thesis.

Example:

R: Christianity universalized moral worth beyond tribe, class, and city.

E

Evidence

Historical evidence, study data, source citation, example, or factual support.

Example:

E: Roman treatment of crucifixion as public humiliation.

Ex

Example

A concrete example used to illustrate a broader point.

Example:

Ex: Paul’s letters show moral concern crossing ethnic boundaries.

Def

Definition

A key definition.

Example:

Def: Liberty = absence of external impediments.

Dist

Distinction

The author separates two things that are often confused.

Example:

Dist: Negative liberty vs positive liberty.
Dist: Moral equality vs political equality.
Dist: Cause vs justification.

This is one of the most useful marks for philosophy, politics, and history.


Chain

Use when the author is building a multi-step argument.

Example:

Chain:
1. Humans are equal before God
2. Therefore all souls have equal worth
3. Therefore hierarchy loses absolute moral authority
4. Therefore modern equality becomes thinkable

4. Critical Thinking Marks

?

Confusing

Use when you do not understand the passage.

Example:

? How is Hobbes different from hard determinism here?

??

Very unclear / needs rereading

Use when the passage is central but difficult.

Example:

?? Need to reread this section before making notes.

C

Counterargument

Use when you think of an objection.

Example:

C: Could this also come from Stoicism, not only Christianity?

CA

Counterargument from author

Use when the author presents the opposing side.

Example:

CA: Enlightenment thinkers rejected Christianity but kept Christian moral assumptions.

W

Weak argument

Use when the author’s reasoning seems thin, selective, overstated, or unsupported.

Example:

W: Claim is too broad; needs comparison with Greek and Roman sources.

Bias?

Use when the author may be framing the evidence ideologically.

Example:

Bias? Author downplays economic causes and overemphasizes theology.

Source?

Use when you want to check where the author got the claim.

Example:

Source? What primary source supports this?

Fact?

Use for claims that need verification.

Example:

Fact? Were Christians really less than 10% of the empire under Constantine?

Over

Use when the author seems to overstate a point.

Example:

Over: “All modern morality comes from Christianity” seems too absolute.

5. Connection Marks

→

Use when the passage connects to another author, book, idea, or debate.

Example:

→ Nietzsche, Genealogy of Morals
→ Siedentop, Inventing the Individual
→ Hobbes vs Locke

↔

Use when two ideas are in tension or should be compared.

Example:

↔ Holland vs Freeman
↔ Paul vs Greek philosophy
↔ Christian equality vs Enlightenment autonomy

X

Use when the passage contradicts another author or something you previously believed.

Example:

X: Contradicts Freeman’s claim about Aquinas.

Bridge

Use when a passage connects two major themes.

Example:

Bridge: Christianity → individualism → liberal rights

Obsidian

Use when the passage should definitely become a note.

Example:

Obsidian: Create note on “Christian Origins of Moral Equality”

You can shorten this to:

Ob

6. Research Marks

Book+

Use when the author mentions a book you may want to add to your reading list.

Example:

Book+: Augustine, City of God
Book+: MacIntyre, After Virtue

Person+

Use for important figures to research.

Example:

Person+: Tertullian
Person+: Grotius
Person+: Leo Strauss

Term+

Use for a concept you need to define later.

Example:

Term+: syneidesis
Term+: natural law
Term+: subsidiarity

Primary

Use when the author cites or discusses a primary source.

Example:

Primary: Romans 2
Primary: Aristotle, Politics
Primary: Locke, Second Treatise

Study

Use when the book references a study, dataset, poll, experiment, or empirical claim.

Example:

Study: Raj Chetty mobility research
Study: Harvard Study of Adult Development

7. Memory and Review Marks

M

Use for something you want to memorize.

Example:

M: “Man is born free, and everywhere he is in chains.”

Q

Use when the passage creates a question for later.

Example:

Q: Is moral equality possible without metaphysical equality?

A

Use when the passage answers a previous question.

Example:

A: This answers why Paul matters for universalism.

Sum

Use when a paragraph summarizes a chapter or section well.

Example:

Sum: Good summary of Hobbes’s political anthropology.

Review

Use for passages that should be reread before writing notes.

Example:

Review: Reread before making permanent note.

8. Emotional / Personal Marks

Use these lightly. They are useful, but they can clutter serious notes.

Me

Use when something applies directly to your life, habits, family, or thinking.

Example:

Me: This applies to learned helplessness and personal agency.

Life

Use for practical wisdom.

Example:

Life: Friendship as central to happiness.

Parent

Use for parenting-related insight.

Example:

Parent: Useful for teaching Ella moral responsibility.

Write

Use for something that could become an essay, Substack post, or longer note.

Example:

Write: Essay idea — “Victimhood, Christianity, and Modern Politics”

9. Page-Level Marks

At the top or bottom of a page, you can add quick page summaries.

Bottom of page

Use a short summary:

p. 142: Author argues Christian moral equality weakened ancient hierarchy.

Top corner

Use symbols for the page’s main value:

★ T C →

Meaning:

  • Important thesis
  • Main argument
  • Counterargument
  • Connection to another book

This makes later review much faster.


10. Chapter-End System

At the end of each chapter, write a small index inside the back blank page, front blank page, or a notebook.

Use this format:

Chapter 4 — Main Notes
 
T: Christianity changed the moral status of the weak.
R: Crucifixion became symbol of divine victory, not shame.
E: Paul, Roman punishment, martyr traditions.
C: Need to compare with Stoicism and Jewish ethics.
→ Nietzsche, Siedentop, Freeman
Ob: Create note on “The Victim as Moral Authority”

This is more valuable than heavy page marking.


11. Inside Back Cover Index

Use the inside back cover as your book-specific index.

Example:

Christian equality — 44, 67, 129, 203
Natural law — 88, 91, 145
Hobbes — 220, 227, 231
Nietzsche — 301, 319, 335
Weak argument — 176, 255
Best summary — 89, 214
Substack ideas — 133, 278, 344

This turns the physical book into a searchable object.


12. Minimal Version

For most reading, you do not need every mark. Use this compact system:

MarkMeaning
[Important passage
UnderlineExact phrase or quote
★Major thesis
TThesis
RReason
EEvidence
DefDefinition
DistImportant distinction
?Confusing
CCounterargument
WWeak argument
Fact?Needs fact-check
→Connection
ObTurn into Obsidian note
QQuestion
SumGood summary
WriteEssay idea

This is probably the version you should use most often.


13. Full System Cheat Sheet

PASSAGE MARKS
[        Important passage / argument unit
|        Useful but secondary passage
underline Exact phrase, definition, quote
circle   Name, date, term, school, concept
 
IMPORTANCE
★        Major thesis
★★       Book-level thesis
!        Important insight
!!       Very important insight
 
ARGUMENT STRUCTURE
T        Thesis
R        Reason
E        Evidence
Ex       Example
Def      Definition
Dist     Important distinction
Chain    Multi-step argument
 
CRITIQUE
?        Confusing
??       Very confusing / reread
C        Your counterargument
CA       Author’s counterargument
W        Weak argument
Bias?    Possible bias
Source?  Check source
Fact?    Verify factual claim
Over     Overstated claim
 
CONNECTIONS
→        Connects to another idea/book/author
↔        Compare with another idea/book/author
X        Contradicts another source
Bridge   Links two big themes
Ob       Turn into Obsidian note
 
RESEARCH
Book+    Add book to reading list
Person+  Research person
Term+    Define concept later
Primary  Primary source mentioned
Study    Study/data/poll cited
 
MEMORY / REVIEW
M        Memorize
Q        Question to answer later
A        Answers previous question
Sum      Good summary passage
Review   Reread before notes
 
PERSONAL / WRITING
Me       Personally relevant
Life     Practical wisdom
Parent   Parenting insight
Write    Essay/Substack idea

14. Recommended workflow while reading

First read

Mark lightly.

Use mostly:

[
underline
★
?
C
→
Ob

Do not overcomplicate while reading.

After each chapter

Review your marks and write:

1. What was the author’s main claim?
2. What were the strongest reasons?
3. What evidence mattered?
4. What do I disagree with?
5. What connects to other books?
6. What should become an Obsidian note?

After finishing the book

Create:

1. One-page memory map
2. Chapter-by-chapter summary
3. List of best quotes
4. List of strongest arguments
5. List of weak claims
6. Obsidian notes for major concepts
7. Reading list generated from the book

15. My recommended default for you

Use this system:

[      = important passage
____   = exact phrase or quote
★      = central thesis
T      = thesis
R      = reason
E      = evidence
Def    = definition
Dist   = distinction
?      = confusing
C      = counterargument
W      = weak argument
Fact?  = fact-check
→      = connects to another book or idea
Ob     = turn into Obsidian note
Write  = essay/Substack idea

That gives you enough structure without making reading feel like paperwork.

The most important rule: bracket ideas, underline words, write why it matters in the margin.

Below is a researched list of book-marking strategies people commonly recommend, from classic “serious reading” systems to academic annotation guides to modern BookTok-style tabbing.

1. Mortimer Adler /

How to Read a Book

system

This is the most influential traditional system. Adler’s method is built around treating reading as an active conversation with the author. His marks are:

MarkUse
Underline / highlightMajor points or forceful statements
Vertical line in marginEmphasize a longer passage or already-underlined point
Star / asteriskThe 10–20 most important statements in the whole book
Numbers in marginTrack the sequence of an argument
Page numbers in marginCross-reference related points elsewhere in the book
Circle key wordsMark important terms or phrases
Margin notesQuestions, answers, summaries, objections, simplifications
Back endpapersPersonal index of the author’s points
Front endpapersFinal outline of the book’s structure

Adler’s core insight is that underlining alone is not enough; the highest-value move is building a personal index and outline inside the book.  

Text link: https://catholicliberaleducation.org/wp-content/uploads/2021/01/How-to-Mark-a-Book-by-Mortimer-Adler-.pdf


2. Farnam Street summary of Adler

Farnam Street repeats Adler’s marking system in a more condensed practical form:

MarkUse
UnderlineMajor points
Vertical margin linesLonger important passages
Stars / asterisksImportant statements
NumbersSequence of points in an argument
Page numbersCross-reference related ideas
CirclesKeywords or phrases
Margin questions / answersDialogue with the author

Their summary also ties marking to Adler’s four reading questions: what the book is about, what is being said in detail, whether it is true, and what follows from it.  

Text link: https://fs.blog/how-to-read-a-book/


3. UNC Learning Center annotation system

UNC’s system is more academic and study-oriented. It emphasizes active comprehension, not just marking attractive sentences.

Mark / methodUse
Summaries in your own wordsCondense key points
CirclesKey concepts and phrases
Brief margin commentsYour thoughts, questions, reactions
?Something unclear or needing further exploration
!Interesting point, connection, or important idea
*Something usable later as evidence or an example
Underline / highlightImportant material, but only mindfully

UNC’s best point: annotation should help you explain the material in your own words, not just decorate the page.  

Text link: https://learningcenter.unc.edu/tips-and-tools/annotating-texts/


4. Murray State / Academic Coaching annotation guide

This guide gives a practical student system and explicitly includes brackets.

Mark / locationUse
PencilPreferred because you can revise temporary or mistaken notes
Check marksUsually “I understand” or “this makes sense”
Question marksConfusing material
StarsImportant material
ArrowsConnections between ideas
BracketsImportant passages or whole ideas
Underline / highlightKey words, phrases, or sentences
Inside front coverCharacter list or key-reference list
Inside back coverThemes, motifs, allusions, images, vocabulary
Top marginQuick plot or page summary
Side/bottom marginsInterpretive notes and questions

This is especially useful for literature, history, and books where you want a running index of themes.  

Text link: https://archive.mscok.edu/Content/Uploads/Murray%20State%20College/files/Academic%20Coaching/Annotation%20Guide.pdf


5. Ryan Holiday / Robert Greene notecard system

Ryan Holiday’s system is not primarily a symbol system. It is a workflow: mark while reading, then extract into notecards organized by theme. He says he writes thoughts on 4×6 notecards and identifies each card by theme or by where it would fit in a project. He credits Robert Greene as the source of the method.  

Mark / methodUse
Underline while readingCapture useful passages
MarginaliaRecord thoughts near the passage
NotecardsExtract ideas after reading
Theme labelsFile notes by concept, project, or chapter
Quote / anecdote cardsSave material for future writing
Project cardsPlace ideas into future essays/books/articles

This is highly relevant if your goal is Obsidian, Substack, or long-term research. The book itself becomes the capture layer; notecards or Obsidian become the permanent system.

Text link: https://ryanholiday.net/the-notecard-system-the-key-for-remembering-organizing-and-using-everything-you-read/


6. Craft Your Content “symbols by category” approach

This approach recommends creating your own reusable symbol system, where each symbol represents a type of note: category, emotion, ideology, agreement, disagreement, uncertainty, or ambivalence. It also suggests drawings, charts, diagrams, and sketches in the margin when visual synthesis helps.  

Mark / methodUse
Custom symbolsDifferentiate types of notes
Category marksTrack recurring themes
Agree / disagree marksRecord your judgment
Unknown / ambivalent marksFlag uncertainty
Doodles / diagramsSynthesize visually
Charts / graphsRepresent structure or comparison

This is less rigid than Adler. It is useful if you read across politics, philosophy, theology, and history and want marks for “Christianity,” “Enlightenment,” “counterargument,” “agency,” “rights,” “statism,” etc.

Text link: https://www.craftyourcontent.com/how-to-write-in-books/


7. Reddit reader systems

Reddit threads show the “normal reader” version of annotation: fewer formal marks, more practical shortcuts.

Common marks people report using:

MarkUse
UnderliningImportant parts
StarsVery important points to return to
CirclesVocabulary or terms to define
Margin notesAnalysis, commentary, symbols, characterization
HighlightsFigurative language, imagery, metaphors, memorable lines
Sticky notes / tabsMark quotes, themes, emotional reactions, or pages to revisit
Margin lineLong section too large to underline
One underlined sentence per pageAvoid over-marking

One commenter’s starter rule is good: do not underline everything; try to identify the sentence that captures the main idea of the page or chapter, and use margin lines or stars for longer sections.  

Text links:
https://www.reddit.com/r/books/comments/tzpgg7/readers_who_annotate_their_books_whyhow_do_you_do/
https://www.reddit.com/r/books/comments/8lyt0y/how_do_you_mark_your_books/


8. BookTok / Bookstagram tabbing systems

Modern social reading communities often use color-coded tabs and pens. The Guardian reported that BookTok and Bookstagram annotation systems frequently use colors to track emotional reactions, plot elements, foreshadowing, romantic moments, character changes, predictions, and reread value.  

Mark / methodUse
Colored tabsThemes, emotions, plot elements
Color-coded pensDifferent types of marginal notes
PredictionsRecord what you think will happen
Emotional reactionsMark shocking, satisfying, sad, funny, or moving passages
Character trackingFollow how your opinion of a character changes
Gift annotationWrite reactions for another reader
Reread tabsMark passages worth revisiting

This is better for fiction, biography, memoir, or books where emotional response and narrative development matter.

Text link: https://www.theguardian.com/books/2025/jun/23/marginalia-mania-how-annotating-books-went-from-big-no-no-to-booktoks-next-trend


Consolidated list of marks people use

MarkCommon meaning
UnderlineImportant sentence, major point, quote
HighlightSame as underline, often for key material
Vertical margin lineImportant longer passage
BracketWhole passage, paragraph, or argument unit
Star / asteriskVery important passage
Double starBook-level importance
CircleKey term, phrase, person, date, vocabulary
BoxKey concept or phrase
?Confusing, questionable, needs follow-up
!Interesting, surprising, powerful, important
*Evidence or example to use later
Check markUnderstood / agreed / useful
ArrowConnection, consequence, movement in argument
NumbersSequence of an argument
Page numberCross-reference related idea elsewhere
Margin noteQuestion, objection, summary, reaction
Top margin notePage summary or location marker
Bottom margin noteInterpretation or longer thought
Front cover notesStructure, thesis, character list, major ideas
Back cover notesIndex of themes, terms, pages, vocabulary
Colored tabsThemes, emotions, plot, claims, quotes
Sticky notesLonger notes without writing directly in the book

Best hybrid system from the research

For your nonfiction reading, I would combine Adler + UNC + Ryan Holiday:

MarkUse
[Bracket full argument or passage
UnderlineExact phrase, definition, or quote
★One of the most important claims in the chapter/book
TThesis
RReason supporting thesis
EEvidence/example
?Confusing or needs research
CCounterargument
WWeak argument
→Connection to another book/idea
Page numberCross-reference
ObTurn into Obsidian note
Back cover indexThemes + page numbers
End-of-chapter note3–6 sentence summary
Post-reading extractionMove strongest ideas into Obsidian

The common pattern across almost every system is this: underline less, write more in the margin, and create some kind of index or extraction system after reading.