Prohibition, Frustration & Refranation

Prohibition, Frustration, and Refranation

The Failure of Perfection in Traditional Astrology

In traditional astrology, an applying aspect is not automatically a promise fulfilled.

Two significators may appear to be approaching conjunction, sextile, square, trine, or opposition, apparently describing an event moving toward completion. Yet before the aspect perfects, something may intervene. Another planet may reach one of the significators first. One of the parties may become occupied with something else. The applying planet may station and turn retrograde. What appeared possible at the moment of judgment can therefore fail before becoming actual.

Traditional astrologers developed a sophisticated vocabulary for these interruptions. Among the most important are prohibition, frustration, and refranation.

These doctrines are especially valuable in horary astrology, where the distinction between application and perfection is fundamental, but they are equally useful in electional astrology. An election containing an apparently favorable application may be much weaker than it first appears if that application is subsequently prohibited, frustrated, or refrained.

The essential principle may be stated simply:

An applying aspect describes a movement toward an event; perfection describes the actual completion of that movement.

Prohibition, frustration, and refranation describe different ways in which the promised perfection can be interrupted.

1. Perfection Comes Before Denial of Perfection

Before identifying any prohibition or frustration, there must first be something capable of being perfected.

Suppose:

• Planet A signifies the querent.
• Planet B signifies the matter sought.
• A is applying to B.

If the aspect would become exact without another event intervening, there is potential for direct perfection.

For example:

Venus 12° Taurus → Jupiter 16° Taurus

Venus is moving toward conjunction with Jupiter.

If Venus reaches Jupiter at 16° Taurus, the conjunction perfects.

But the astrologer must not stop at the observation that Venus is applying. The entire sequence of planetary motion must be examined.

Questions must include:

• Does another planet reach Jupiter first?
• Does Jupiter perfect another aspect first?
• Does Venus station before reaching Jupiter?
• Does either planet change sign?
• Does retrogradation alter the sequence?
• Is another planet translating or collecting the light?
• Does reception preserve or modify the promised outcome?

Traditional judgment is therefore inherently dynamic.

The chart is not simply a picture.

It is a sequence of events.

2. Prohibition

Definition

Prohibition occurs when two significators are applying toward perfection, but another planet intervenes and perfects an aspect with one of the relevant planets before the intended significators can complete their own aspect.

The third planet effectively gets there first.

William Lilly describes prohibition as occurring when two planets signify the completion of a matter and are applying, but another planet interposes by conjunction or aspect before their application can perfect.

Conceptually:

A → B

appears to promise perfection.

But:

C → B

perfects first.

The perfection of A with B is therefore prohibited.

3. The Logic of Prohibition

Imagine a horary question:

“Will I obtain the position?”

Let:

• Mercury = querent
• Jupiter = employer or position

Mercury applies to Jupiter.

At first sight, this appears promising.

But suppose Venus also applies to Jupiter and Venus perfects her aspect first.

The symbolism becomes:

Mercury → Jupiter
but
Venus → Jupiter first

Venus may represent:

• another applicant,
• another contractual obligation,
• another employee,
• another offer,
• another person influencing the employer,
• or simply an intervening circumstance.

The important fact is not merely that Venus aspects Jupiter.

It is that Venus reaches Jupiter before Mercury does.

Chronology is essential.

4. Prohibition Is Not Merely “A Bad Aspect”

This distinction is extremely important.

A square from a malefic somewhere in the chart is not automatically prohibition.

Neither is every intervening aspect.

For genuine prohibition, there must be an existing potential perfection whose completion is interrupted.

The proper sequence is:

1. Identify the significators.
2. Confirm that they are applying toward perfection.
3. Calculate when that perfection would occur.
4. Examine whether another relevant planetary contact perfects first.
5. Determine whether that event truly interferes with the promised perfection.

Without the initial application, there is technically nothing to prohibit.

5. Prohibition by Conjunction and by Aspect

Traditional authors allow prohibition through both bodily conjunction and aspect.

Suppose Mars and Saturn are applying toward conjunction:

Mars 7° Aries
Saturn 12° Aries

But the Sun is behind Mars and moving faster:

Sun 6° Aries

If the Sun overtakes Mars and reaches Saturn before Mars does, the Sun prohibits the Mars–Saturn perfection.

The same principle can operate through aspects rather than conjunction.

For example:

• Mercury applies to trine Jupiter.
• Venus also applies to sextile Jupiter.
• Venus perfects first.

Venus may prohibit the Mercury–Jupiter perfection.

The geometry differs, but the principle is identical:

Another planetary action reaches the intended recipient first.

6. Does Prohibition Always Mean Absolute Failure?

Not necessarily.

This is one of the most important refinements in serious traditional practice.

Prohibition is often taught as:

“Another planet intervenes, therefore the answer is no.”

That is too mechanical.

Earlier traditional discussions allow circumstances in which prohibition may describe delay, obstruction, competition, mediation, or a condition that must first be satisfied, rather than irrevocable destruction.

The astrologer should examine:

• reception,
• essential dignity,
• accidental strength,
• the houses ruled by the prohibiting planet,
• whether the prohibitor is benefic or malefic,
• whether the original significators later regain contact,
• and whether another form of perfection subsequently emerges.

A well-received benefic prohibition can behave differently from a hostile malefic prohibition.

For example:

“Will the bank approve my purchase?”

Suppose the buyer’s significator applies to the seller, but Saturn representing legal documentation reaches the seller first.

This might signify:

“The transaction cannot proceed until the legal requirements are satisfied.”

That is prohibition in the literal sense, but not necessarily permanent denial.

The event may be conditional.

7. Reception Changes the Meaning of Prohibition

Reception is one of the most important diagnostic tools.

Suppose the prohibiting planet strongly receives the relevant significator.

The intervention may be:

• protective,
• procedural,
• mediating,
• necessary,
• or even ultimately helpful.

Without reception, especially where the prohibitor is debilitated or hostile toward the significators, the obstruction is more likely to be damaging.

Thus:

Prohibition describes the mechanism; reception helps describe the intention and outcome of the mechanism.

This distinction prevents crude judgment.

8. Frustration

Frustration is closely related to prohibition, but its classical usage requires more care because the terminology changed between medieval and early-modern authors.

In the form familiar from William Lilly:

Frustration occurs when a faster significator is applying to a slower significator, but the slower significator perfects with another planet before the applying significator can reach it.

Lilly’s famous example places:

• Mercury at 10° Aries
• Mars at 12° Aries
• Jupiter at 13° Aries

Mercury attempts to conjoin Mars.

But Mars reaches Jupiter first.

Thus Mercury is frustrated.

The symbolism is beautifully summarized by Lilly through the proverb:

two contend for something, while a third obtains it.

The essential psychological difference from ordinary prohibition is useful:

Prohibition: another planet prevents the intended union.

Frustration: the planet being pursued becomes engaged elsewhere before the pursuer reaches it.

9. The Difference Between Prohibition and Frustration

Consider two scenarios.

Prohibition

A applies to B.

C also approaches B and reaches B first.

C intercepts the intended perfection.

Symbolically:

“Something gets in the way.”

Frustration

A applies to B.

But B moves into perfection with C before A reaches B.

The intended recipient becomes occupied elsewhere.

Symbolically:

“The thing you were pursuing goes elsewhere.”

This difference can be remarkably descriptive in actual horary charts.

10. Practical Examples of Frustration

Relationship

A person asks:

“Will this relationship develop?”

Venus signifies the querent and Mars the desired partner.

Venus applies to Mars.

But Mars perfects a conjunction with Jupiter first.

This might indicate:

• another relationship,
• another priority,
• travel,
• work,
• family obligations,
• or another Jupiterian circumstance attracting Mars away.

The meaning is not merely “obstacle.”

The desired party is drawn into another perfection first.

Employment

Mercury signifies the applicant.

Saturn signifies the employer.

Mercury applies to Saturn.

But Saturn perfects with Venus before Mercury reaches it.

Venus could represent another candidate.

The position may therefore be filled first.

Property

The querent’s significator applies to the ruler of the fourth house.

Before perfection, the fourth-house ruler perfects with another planet.

Another buyer may secure the property.

This is a classic manifestation of frustration:

the desired object becomes committed elsewhere.

11. Historical Caution Concerning “Frustration”

The modern student should know that frustration is not a perfectly stable technical term across the history of astrology.

Arabic and medieval Latin authors described several closely related forms of interrupted perfection under concepts translated as:

• evasion,
• abscission,
• cutting of light,
• prevention,
• return of light,
• frustration.

William Lilly reorganized some of these older categories.

Consequently, what one traditional author calls frustration may be classified differently by another.

For modern practical work, Lilly’s definition is convenient and widely used:

The sought significator perfects with another planet before the pursuing significator reaches it.

But when reading Bonatti, Abu Maʿshar, al-Biruni, Dariot, Schoener, or other medieval authors, one should not assume that every technical term corresponds perfectly to Lilly’s vocabulary.

The underlying astronomical sequence is more important than the label.

12. Refranation

Definition

Refranation occurs when a planet is applying toward perfection but turns retrograde before the aspect becomes exact, thereby withdrawing from the intended perfection.

This is fundamentally different from prohibition and frustration.

No third planet is required.

The applying planet itself changes its motion.

For example:

Mars 7° Aries → Saturn 12° Aries

Mars appears to be applying toward conjunction with Saturn.

But Mars stations at 10° Aries and turns retrograde.

Instead of continuing toward Saturn, Mars begins moving backward.

The conjunction never perfects.

Mars has refrained.

13. The Symbolism of Refranation

Of the three conditions, refranation often produces the clearest symbolism.

The planet that was moving toward the event changes direction.

It can therefore signify:

• withdrawal,
• reconsideration,
• refusal,
• cancellation,
• loss of confidence,
• change of mind,
• reversal of policy,
• retreat,
• abandonment,
• or circumstances forcing the actor to turn back.

Bonatti compared the condition to restraining a galloping horse by pulling the reins so that it no longer reaches its intended destination.

This metaphor captures refranation perfectly:

The movement existed. The destination was real. But the journey was abandoned before arrival.

14. Refranation Is Stronger Than Ordinary Retrogradation

A retrograde significator by itself does not necessarily constitute refranation.

The sequence matters.

To have refranation:

1. An application toward perfection must exist.
2. The applying planet must be moving toward the exact aspect.
3. It must station before perfection.
4. It must turn retrograde.
5. The reversal must prevent the aspect from becoming exact.

Thus:

retrograde ≠ automatically refranation

Refranation is a specific dynamic event.

15. Who Changes Their Mind?

The planet that refrains usually tells the astrologer which party withdraws.

Suppose:

• L1 = querent
• L7 = potential partner

If L1 applies toward L7 but L1 stations retrograde first:

the querent may withdraw.

If L7 is the applying planet and L7 refrains:

the partner may withdraw.

This is one reason exact planetary dynamics are so valuable in horary astrology.

They do not simply predict whether something happens.

They can describe who prevents it and how.

16. Refranation Does Not Always Mean Psychological Choice

A common oversimplification is:

“Refranation means someone changes their mind.”

Sometimes it does.

But a planet’s reversal can also describe circumstances forcing reversal.

For example:

A company intends to hire someone but loses its budget.

The employer’s significator may refrain.

The symbolic reversal belongs to the employer, even if no emotional hesitation was involved.

Likewise:

• funding may be withdrawn,
• permission may be revoked,
• travel may be cancelled,
• an order may be reversed,
• illness may force retreat,
• market conditions may change.

The natal condition, houses ruled, reception, and context must determine what the retrogradation represents.

17. Refranation Versus Evasion

These two are frequently confused.

Refranation

The applying planet turns retrograde before perfection.

Evasion

The receiving planet changes sign before the applying planet can reach it.

These describe entirely different mechanisms.

Refranation:

“I was coming, but I turned back.”

Evasion:

“You were coming, but I left before you arrived.”

This distinction is exceptionally useful in relationship, contractual, legal, and employment questions.

18. Prohibition, Frustration, and Refranation Compared

These distinctions are more useful than reducing all of them to a generic “no.”

Each condition describes a different narrative.

19. The Importance of Planetary Speed

These doctrines cannot be judged properly without planetary speed.

The astrologer must know not merely the zodiacal positions of the planets, but their actual motion.

Consider:

• Mercury at 10°
• Venus at 11°
• Mars at 15°

Simply looking at longitude is insufficient.

Mercury may be:

• unusually slow,
• stationary,
• preparing to retrograde.

Venus may therefore reach Mars before Mercury despite appearing less favorably positioned.

Likewise, a superior planet may itself be retrograde and moving toward an unexpected perfection.

The correct question is:

Which exact aspect occurs first in real planetary motion?

Not:

“Which planet visually looks closest?”

This is especially important when dealing with Mercury, Venus, and Mars near their stations.

20. Stations Must Be Examined Precisely

A planet within a few degrees of perfection may appear almost certain to complete an aspect.

But if it is approaching station, the application can be deceptive.

An astrologer should therefore check:

• current daily motion,
• station time,
• exact time of perfection,
• sign ingress,
• retrograde/direct station,
• and intermediate aspects.

A difference of only a few hours may completely alter judgment.

This is why reliable ephemerides are indispensable in advanced horary and electional astrology.

21. Sign Boundaries Matter

Applications near 29° deserve special attention.

Suppose:

Venus 27° Gemini → Mars 1° Cancer

Simply measuring four degrees of longitude can be misleading.

A classical aspect cannot automatically be assumed across every sign transition.

The astrologer must determine:

• whether the aspect actually forms after ingress,
• whether the signs support the intended aspect,
• whether another aspect occurs first,
• whether reception changes after ingress,
• and whether the change of sign itself represents a radical change of circumstances.

An apparent perfection may disappear completely once actual zodiacal geometry is followed.

22. Reception Can Rescue, Modify, or Explain Failure

A prohibition should never be interpreted independently of reception.

Suppose Jupiter prohibits Venus from perfecting with Mars.

If Jupiter:

• strongly receives Venus,
• rules a helpful house,
• and is essentially dignified,

Jupiter may represent a legitimate mediator rather than an enemy.

For example:

• a lawyer,
• manager,
• parent,
• institution,
• broker,
• physician,
• authority,
• or necessary intermediary.

Conversely, a debilitated malefic prohibiting without reception may represent genuine destructive interference.

Reception therefore helps answer:

Why is this planet intervening?

23. Benefics Do Not Automatically Help

Venus or Jupiter can prohibit just as Mars or Saturn can.

A benefic third planet is not automatically beneficial merely because of its natural nature.

Suppose Jupiter signifies another buyer who obtains the house before the querent.

Jupiter may be benefic naturally, but functionally it deprives the querent of the property.

Similarly, Venus may signify another romantic interest who intervenes in a relationship.

Traditional judgment therefore requires contextual rulership.

Always ask:

What does this planet signify in this chart?

before asking:

“Is it naturally benefic or malefic?”

24. Malefics Do Not Automatically Destroy

The reverse is equally important.

Saturn may represent:

• a judge,
• an official,
• an employer,
• a boundary,
• a contract,
• an elderly person,
• land,
• bureaucracy,
• or necessary restriction.

Mars may signify:

• surgery,
• technical intervention,
• military authority,
• competition,
• or decisive action.

If such planets prohibit, they may describe procedures that must occur before completion.

Natural temperament matters, but house rulership, reception, dignity, and context come first.

25. Translation and Collection Can Change the Verdict

A direct application may fail, yet another perfection may subsequently appear.

Suppose L1 and L7 fail to perfect because of prohibition.

But the Moon:

1. separates from L1,
2. then applies to L7,
3. carrying the light between them.

The matter may still be accomplished by translation of light.

Likewise, both significators may apply to a slower third planet which receives and collects their light.

Therefore:

The failure of one perfection is not necessarily the failure of the entire chart.

The astrologer must inspect the complete chain of applications.

26. The Moon Requires Special Attention

In horary astrology the Moon frequently reveals the unfolding narrative even when she is not one of the primary house rulers.

Her:

• last aspect,
• present condition,
• immediate application,
• subsequent applications,
• translation of light,
• prohibition,
• reception,
• and final aspect before leaving the sign

may all materially alter the judgment.

A direct L1–L7 application that appears prohibited may still be restored through lunar translation.

Conversely, an apparently promising application may be undermined if the Moon first encounters a severe obstruction.

The Moon therefore belongs to the chronology of perfection, not merely to the background symbolism of the chart.

27. Application Within Orb Is Not Enough

A common technical error is to say:

“The planets are within orb, therefore they perfect.”

Orb establishes the possibility of engagement.

It does not prove completion.

A valid analysis requires:

Application + uninterrupted motion + actual exact perfection

The planets may be within moiety and strongly applying yet still:

• refrain,
• evade,
• become prohibited,
• become frustrated,
• encounter another planet,
• change sign,
• or lose the aspect entirely.

The distinction between application and perfection is one of the foundations of traditional astrology.

28. Applying Versus Separating Third Planets

Another frequent mistake is identifying prohibition from an aspect that has already happened.

Suppose Mercury has already separated from Jupiter.

The Sun now applies to Jupiter.

Mercury does not normally prohibit merely because Mercury recently contacted Jupiter.

The astrologer must distinguish:

what has already occurred

from

what will occur before the intended perfection.

Prohibition concerns future interference in the chain of application.

Chronology is therefore more important than the static aspect table.

29. A Practical Analytical Procedure

When judging potential perfection, use the following sequence.

Step 1 — Identify the relevant significators

Determine:

• L1,
• ruler of the quesited house,
• Moon,
• and any legitimate additional significators.

Do not begin with random aspects.

Step 2 — Identify the intended perfection

Ask whether the principal significators:

• conjoin,
• sextile,
• square,
• trine,
• oppose,
• translate light,
• or collect light.

Step 3 — Determine which planet is applying

Establish the actual direction of motion.

Do not infer application merely from zodiacal positions.

Step 4 — Calculate the exact perfection

Determine approximately when the intended aspect becomes exact.

Step 5 — Examine every earlier relevant event

Before perfection, check for:

• conjunctions,
• Ptolemaic aspects,
• stations,
• retrogradation,
• sign ingress,
• translation,
• collection,
• prohibition,
• frustration,
• refranation,
• and evasion.

Step 6 — Identify the intervening planet

If a third planet interferes, examine:

• its house rulership,
• natural significations,
• essential dignity,
• accidental dignity,
• reception,
• sect where relevant,
• retrogradation,
• combustion,
• and relationship with the primary significators.

Step 7 — Decide whether the result is denial or delay

Do not assume every prohibition destroys perfection permanently.

Look for subsequent recovery.

Step 8 — Translate the celestial mechanism into narrative

Do not merely write:

“Prohibition = no.”

Instead say:

“A third party represented by Venus intervenes before the employer can complete the agreement with the querent.”

The technique becomes meaningful only when astronomical structure is translated into concrete symbolism.

30. Use in Electional Astrology

These doctrines are extremely useful in electional astrology.

An election may contain a desirable application such as:

• L1 applying to L10 for professional success,
• L1 applying to L7 for partnership,
• Moon applying to Jupiter,
• Moon applying to Venus,
• significator applying to its dispositor.

But the astrologer must inspect what happens before the intended aspect perfects.

If another planet prohibits it, the election may encode precisely the kind of obstruction the election was intended to avoid.

31. Prohibition in Elections

Suppose an election for a business agreement has:

• L1 applying to L7,
• but Saturn reaches L7 first.

If Saturn rules the house of debts, losses, restrictions, or litigation, this deserves serious concern.

The election may describe:

the agreement being delayed or intercepted by a Saturnian condition.

Whenever possible, choose a time where the intended significators can perfect cleanly.

32. Refranation in Elections

Refranation is generally undesirable when the election depends upon completion.

Examples include:

• signing contracts,
• beginning partnerships,
• launching commercial enterprises,
• making proposals,
• submitting applications,
• commencing journeys,
• beginning negotiations.

An applying significator that stations retrograde before perfection symbolically embeds reversal into the elected action.

Such an election may produce:

• renegotiation,
• withdrawal,
• cancellation,
• repeated work,
• reversal,
• or inability to reach the intended conclusion.

Unless reversal itself is desired, this condition is usually best avoided.

33. There Are Exceptions

Traditional electional astrology is not governed by simplistic universal prohibitions.

Sometimes the desired operation itself involves:

• undoing,
• returning,
• recovering,
• revisiting,
• withdrawing,
• reversing,
• dissolving,
• restoring,
• or correcting something previously begun.

In such situations retrogradation can occasionally participate meaningfully in the election.

But this should be intentional.

One should not accidentally elect refranation into an operation whose goal is straightforward completion.

34. Do Not Treat the Three Conditions as Synonyms

The temptation to translate all three as “something goes wrong” loses much of traditional astrology’s diagnostic power.

They describe three distinct stories.

Prohibition

“You were moving toward the result, but something intervened.”

Frustration

“You were moving toward the result, but the thing you wanted became engaged elsewhere.”

Refranation

“You were moving toward the result, but you reversed direction before reaching it.”

This narrative distinction is often more valuable than the yes/no judgment itself.

35. Strength of Testimony

Not every prohibition deserves equal weight.

A strong judgment considers:

Exactness

How clearly does the interfering perfection occur before the intended one?

Relevance

Does the third planet rule something directly connected to the question?

Reception

Is the interference welcomed, tolerated, rejected, or hostile?

Dignity

Can the intervening planet actually accomplish what it signifies?

House position

Is it angular and capable of acting strongly, or cadent and weak?

Planetary condition

Is it:

• direct,
• retrograde,
• swift,
• slow,
• combust,
• under the beams,
• cazimi,
• stationary?

Subsequent motion

Does the original perfection become possible again later?

These factors distinguish decisive denial from temporary obstruction.

36. A Hierarchy of Interpretation

A useful practical hierarchy is:

First: Does perfection exist?

If not, there is nothing to prohibit.

Second: Does anything interrupt perfection?

Follow actual planetary motion.

Third: What kind of interruption is it?

Identify prohibition, frustration, refranation, evasion, or another form of denial.

Fourth: Who causes it?

Read the relevant planet through house rulership.

Fifth: Why?

Use reception, dignity, and planetary condition.

Sixth: Is the interruption final?

Search for subsequent perfection.

This method produces much more reliable judgment than memorizing isolated definitions.

37. Common Errors

Error 1 — Calling every intervening aspect prohibition

Only aspects occurring before the promised perfection and capable of interfering with it are relevant.

Error 2 — Ignoring planetary speed

Degree position alone cannot determine which perfection happens first.

Error 3 — Calling every retrograde planet refranation

The planet must first be applying and then turn retrograde before perfection.

Error 4 — Ignoring reception

The same geometric prohibition can indicate obstruction, mediation, protection, or delay depending upon reception.

Error 5 — Treating benefics as automatically helpful

A benefic can represent the competitor who obtains what the querent wanted.

Error 6 — Treating malefics as automatically destructive

A malefic may signify a necessary authority or condition.

Error 7 — Stopping after the first failure

Translation or collection may later restore perfection.

Error 8 — Ignoring sign changes

Ingress can completely alter aspect geometry, dignity, reception, and symbolism.

Error 9 — Confusing historical terminology

Medieval and Renaissance authors do not always classify forms of denied perfection identically.

Study the astronomical mechanism first and terminology second.

38. Recommended Practice for Traditional Astrologers

For serious horary and electional work:

1. Never judge from an aspect grid alone.
2. Track the planets forward in real motion.
3. Check exact perfection times.
4. Inspect stations and sign ingresses.
5. Identify every perfection occurring first.
6. Read the intervening planet through house rulership.
7. Use reception to determine the quality of interference.
8. Examine dignity to determine whether the interfering planet has power to act.
9. Check whether translation or collection subsequently restores perfection.
10. Distinguish delay from complete denial.
11. Use historical terminology carefully.
12. Describe the event symbolically rather than reducing the technique to a binary rule.

39. Final Principle

Prohibition, frustration, and refranation belong to one of the most sophisticated ideas in traditional astrology:

Potential is not the same as completion.

An applying aspect tells us that two significators are moving toward an encounter.

But astrology asks a more difficult question:

Do they actually get there?

Prohibition answers:

Something reaches the matter first.

Frustration answers:

The thing being sought becomes engaged elsewhere.

Refranation answers:

The pursuing force reverses before arrival.

The value of these doctrines lies not merely in producing negative judgments. Their real value is diagnostic. They reveal where the chain of causation breaks.

For this reason, the advanced astrologer should never read an applying aspect in isolation. Planetary motion must be followed forward until the intended perfection either occurs or fails.

The chart must be read as a sequence.

And in traditional astrology, the sequence of events is often the difference between a promise and its fulfillment.

Historical Note

The terminology surrounding denied perfection developed over many centuries and is not entirely uniform. Important treatments occur in the works associated with Māshāʾallāh, Abū Maʿshar, al-Bīrūnī, Guido Bonatti, Johannes Schoener, Claude Dariot, and William Lilly.

Lilly’s Christian Astrology became particularly influential in modern English-language horary practice, but his organization of prohibition, frustration, and related forms of denied perfection does not reproduce every medieval distinction exactly.

For scholarly work, it is therefore preferable to distinguish between:

• the astronomical mechanism,
• the symbolic interpretation,
• and the historical name given to that mechanism by a particular author.

This approach preserves the precision of the traditional doctrine while avoiding the false assumption that several centuries of astrological literature used an entirely uniform technical vocabulary.

Recommended Classical Sources

• William Lilly — Christian Astrology (1647), especially the chapters concerning application, separation, prohibition, refranation, translation, reception, and frustration.
• Guido Bonatti — Liber Astronomiae, particularly the sections concerning perfection, prohibition, reception, and the cutting or return of light.
• Abū Maʿshar — works dealing with application, reception, and the interruption of perfection.
• al-Bīrūnī — The Book of Instruction in the Elements of the Art of Astrology.
• Claude Dariot — A Brief and Most Easie Introduction to the Astrologicall Judgement of the Starres.
• Johannes Schoener — Opusculum Astrologicum.

These texts should be compared rather than treated as interchangeable, because the classification of denied perfection changes subtly across the medieval and Renaissance traditions.