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July 25, 2013 / A

Memory structures

From The Design of Everyday Things, p. 127 (emphasis added):

Conscious thought is severely limited by the small capacity of short-term memory. Five or six items is all that can be kept available at any one moment. But subconscious thought is one of the tools of the conscious mind, and the memory limitation can be overcome if only an appropriate organizational structure can be found. Take fifteen unrelated things and it is not possible to keep them in conscious memory at once. Organize them into a structure and it is easy, for only that one structure has to be kept in conscious memory. As a result of this power of organization to overcome the limits of working memory, explanation and understanding become essential components of conscious thought: with understanding and explanation, the number of things that can be kept consciously in mind expands enormously.

As coda to this post, I’ve had a much easier time retaining that block of rules. I acknowledge that part of the reason for that might be that I’ve focused on that block exclusively; if I tried analyzing other blocks in that way, perhaps I’d have a harder time. But for the time being, I’m content in knowing that I’ve made a troublesome passage a little easier.

July 25, 2013 / A

Memory and Ali Baba

From The Design of Everyday Things, p. 61-62:

Remember the story of “Ali Baba and the forty thieves?” Ali Baba discovered the secret words that opened the thieves’ cave. His brother-in-law, Kasim, forced him to reveal the secret. Kasim then went to the cave.

“When he reached the entrance of the cavern, he pronounced the words, Open Simsim!

“The door immediately opened, and when he was in, closed on him. In examining the cave he was greatly astonished to find much more riches than he had expected from Ali Baba’s relation. He quickly lade at the door of the cavern as many bags of gold as his ten mules could carry, but his thoughts were now so full of the great riches he should possess, that he could not think of the necessary words to make the door open. Instead of Open Simsim! he said Open Barley! and was much amazed to find that the door remained shut. He named several sorts of grain, but still the door would not open.

“Kasim never expected such an incident, and was so alarmed at the danger he was in that the more he endeavoured to remember the word Simsim the more his memory was confounded, and he had as much forgotten it as if he had never heard it mentioned.”

Kasim never got out. The thieves returned, cut off Kasim’s head, and quartered his body.

I’ve encountered something similar in the Ashtadhyayi, but nothing so drastic as poor Kasim. Sometimes a rule will float at the edge of my memory and bound out of reach when I try to recall it forcefully. Instead it’s often easier to just wait for the rule to come to me.

July 24, 2013 / A

Unusual imperatives

As I go ever nearer to the sharp descent of chapter 6.4 and book 6, I’ve had the fortune to stumble across a piece of Sanskrit morphology that I had wondered about for some time: the many sound changes involved in “regular” verbs (सार्वधातुक), especially the imperatives:

  • पच (पच्)
  • सुनु (सु)
  • आप्नुहि (आप्)
  • धेहि (धा)
  • एधि (अस्)
  • कुरु (कृ)
  • लुनीहि (लु)

Relevant rules

6.4.101 हुझल्भ्यो हेर् धिः
After हु and roots ending in consonants, हि is replaced by धि.
6.4.104 चिणो लुक्
चिण् is deleted by लुक्, as are the following:
6.4.105 अतो हेः
हि after the vowel अ;
6.4.106 उतश् च प्रत्ययाद् असंयोगपूर्वात्
and the same after the vowel उ, if the vowel ends a suffix and is not preceded by a conjunct.
6.4.119 घ्वसोर् एद्धावभ्यासलोपश्च
The last part of the घु verbs and अस् is replaced by ए when followed by हि, and the अभ्यास is deleted as well.

6.4.101 explains the धि in एधि. (This is in the असिद्धवत् section of the Ashtadhyayi, so rules in this section — including the one that changes अस् to ए — are treated as if they didn’t take effect.) 6.4.105 explains पच. 6.4.106 explains सुनु and आप्नुहि. 6.4.119 explains धेहि and एधि.

कुरु and लुनीहि are explained by two other rules:

6.4.110 (करोतेः) अत उत् सार्वधातुके
The अ of the verb कृ is replaced with उ when followed by a सार्वधातुक affix with indicatory क् or ङ्.
6.4.113 ई हल्य् अघोः
The final आ of either श्ना or an अभ्यस्त is replaced with ई when followed by the same.

At the risk of boring the reader, I leave the discussion here. These rules — from about 6.4.101 to 6.4.128 — all account for a variety of interesting transformations.

July 23, 2013 / A


There are few things more humbling than forgetting a group of rules, especially one that endured for a long time. Somehow the sounds and contours they summon to the mind evaporate to high heaven — or worse, perhaps, some shards of them all still remain, as incontrovertible reminder that I had once bolted them to the Sanskritic part of my mind and body.

Yet in such a task as this, with a beguiling horizon that inches ever nearer, there is no choice but to endure. And so it’s been these past few weeks, with block after block slipping through my mind’s grasp and rolling back down to the start.

For a moment I’d like to dwell on one of these blocks and diagnose the things that make it so slippery to grasp.

3.3.151 – 3.3.160

The block is as follows:

3.3.151 शेषे लृडयदौ
3.3.152 उताप्योः समर्थयोर्लिङ्
3.3.153 कामप्रवेदनेऽकच्चिति
3.3.154 सम्भवानेऽलमिति चेत् सिद्धाप्रयोगे
3.3.155 विभाषा धातौ सम्भावनवचनेऽयदि
3.3.156 हेतुहेतुमतोर्लिङ्
3.3.157 इच्छार्थेषु लिङ्लोटौ
3.3.158 समानकर्तृकेषु तुमुन्
3.3.159 लिङ् च
3.3.160 इच्छार्थेभ्यो विभाषा वर्तमाने

So far the following stands out:

  • I hardly know what any of these rules mean anymore.
  • I confuse these rules with other similar rules (e.g. लिङ् यदि).
  • I confuse certain rules with rules that feature similar terms (e.g. तुमुन्).
  • These rules are about relatively minor grammatical points.

So let me go through them slowly below.

The rules


3.3.151 शेषे लृडयदौ
ऌट् is used with words other than यच्च, यत्र, and यदि to denote astonishment.

Astonishment (चित्रीकरण) comes from 3.3.150. This rule expands the scope of the future tense (ऌट्). An example:

आश्चर्यं चित्रम् अद्भुतम् अन्धो नाम पर्वतम् आरोक्ष्यति, बधिरो नाम व्याकरणम् अध्येष्यते
Astonishing indeed, that a blind man will climb the mountain, that a deaf one will study grammar.


3.3.152 उताप्योः समर्थयोर्लिङ्
लिङ् is used along with उत and अपि in the sense those two words share.

This is a weird little rule, and weirdly phrased, that allows लिङ् when used with an affirmative word. Thus उत कुर्यात् “yes, he may do it.”


3.3.153 कामप्रवेदनेऽकच्चिति
लिङ् is also used with words that indicate an expression of desire, except for कच्चित्.

Thus कामो मे भुञ्जीत भवान् “It’s my wish that you eat.”

As an aside, I’m surprised to see that I’ve been memorizing this rule incorrectly, having read कच्चित् instead of the correct कच्चिति.


3.3.154 सम्भवानेऽलमिति चेत् सिद्धाप्रयोगे
लिङ् is used in the sense of possibility/expectation if अलम् is expressed implicitly.

The Kashika has three examples:

  • अपि पर्वतं शिरसा भिन्द्यात् “It’s expected that he’ll break the mountain with his head.” सम्भावन is expressed, as is the sense of अलम्.
  • विदेशस्तायी देवत्तः प्रायेण गमिष्यति ग्रामम् It’s expected that Devadatta, who’s living away, will eventually return to the village.” सम्भावन is expressed, but अलम् is not present.
  • अलं देवदत्तो हस्तिनं हनिष्यति “Devadatta can kill the elephant.” सम्भावन is expressed, but the sense of अलम् is implicit.


3.3.155 विभाषा धातौ सम्भावनवचनेऽयदि
But preferably not when used with a root expressing the sense of सम्भावन, as long as यद् is not used.

Such roots include सम्भावि (causative) and अवकल्पि (causative).


3.3.156 हेतुहेतुमतोर्लिङ्
And preferably not when cause and effect are denoted.

Thus दक्षिणेन चेद् यायात् / यास्यति न शकटं पर्याभवेत् / पर्याभविष्यति “If he goes on the right side, the cart won’t overturn.”


3.3.157 इच्छार्थेषु लिङ्लोटौ
With words denoting a wish/desire, लिङ् or लोट् are used.

लोट् is the command form, as in भवतु, विजयताम्, लभस्व, and so on. This rule sets up the following:


3.3.158 समानकर्तृकेषु तुमुन्
When used with a word denoting the same agent (and that also denotes a wish/desire), तुमुन् can be used too.

Thus इच्छति भोक्तुम् “He wants to eat.”


3.3.159 लिङ् च
लिङ् is used this way as well.

I confuse this with the similar rule लिङ् यदि, which has nearly the same meaning. I guess I’ll just have to my best here. Maybe I can connect च with the च्छ् of इच्छा in the rules above and below.


3.3.160 इच्छार्थेभ्यो विभाषा वर्तमाने
And preferably not after roots that denote a desire/wish when they express the present tense.

Thus इच्छति is preferred over इच्छेत्. इच्छति comes from 3.2.123 वर्तमाने लट्.


I think these rules might sit a little more firmly than before. I’ve forgotten them countless times already, but perhaps next time I might have enough dexterity to restrain them.

July 19, 2013 / A


At first glance Sanskrit is a language with millions of different words. This is part of the reason that Sanskrit seems so intimidating at first. But as we learn more about the language, we see that these millions of words are closer to thousands of words, and that the bewildering forms we’ve seen in the past are formed according to basic patterns. Thus the -अ nouns, though their stems are very different, form words in the same way:

  • गजेन
  • ऐरावतेन
  • इन्द्रप्रस्थेन
  • वेदान्तेन
  • जनकतनयास्नानपुण्योदकेन

There are several patterns like this, and each pattern governs at least a few nouns.

But there is one noun that doesn’t have a single pattern. Although it is very similar to other nouns, there is no other noun like it in Sanskrit. As you might have guessed, that noun is स्त्री (“woman”).

What makes this word so special? A special rule in the Ashtadhyayi, which gives it two additional forms. First, some background:


Chapter 6.4 of the Ashtadhyayi focuses on the अङ्ग, the basic form to which suffixes are added. (In fact, its first rule is just अङ्गस्य, which governs the rules that follow.) It governs a variety of insertions, deletions, and substitutions that coordinate various pieces of grammatical matter into a single word. Among the chapters I’ve read so far, it’s the most “low-level” part of the Ashtadhyayi.

Among other rules, 6.4 contains this bit of internal sandhi:


6.4.77 अचि श्नुधातुभ्रुवां य्वोर् इयङुवङौ
Before any vowel, the vowels इ, ई, उ, and ऊ are replaced, respectively, with इय् and उव् if they are at the end of (1) श्नु, (2) a धातु, or (3) the word भ्रू.

This is why we have words like आप्नुवन्ति, धियः, and भ्रुवौ instead of *आप्न्वन्ति, ध्यः, and भ्र्वौ. These rules also apply to a variety of nouns that are derived directly from verb roots:

  • नी
  • ली
  • श्री
  • पू
  • भू

A later rule extends the scope of 6.4.77 to स्त्री as well:


6.4.79 स्त्रियाः
(This substitution also occurs) for स्त्री.

I suppose this rule is pretty straightforward. It gives us forms like स्त्रियम् and स्त्रियाः instead of *स्त्र्यम् or *स्त्र्याः. But now we come to the rule of intererst:


6.4.80 वांशसोः
But optionally before अम् and शस्.

If you’re unfamiliar with the Ashtadhyayi, take a moment to work out what’s going on here. 6.4.77 states a general principle. 6.4.79 extends that principle to स्त्री, so we can lump those two rules together. And 6.4.80 states that the general principle is optional for स्त्री when followed by अम् or शस्. Unfortunately, we have to bring in one more rule to figure out what sorts of forms 6.4.80 gives us:


We bring in 6.4.101 for context:

6.4.101 अकः सवर्णे दीर्घः
Two similar vowels combine and become long.

Then 6.4.102 for the general combination rule:

6.1.102 प्रथमयोः पूर्वसवर्णः
In the first two (noun cases), (two vowels) (not necessarily homogeneous) combine and the result is similar to the first (and long).

There are many exceptions to 6.1.102, but they don’t apply here.

With 6.1.102 in hand, we see that we can derive the extra forms स्त्रीम् and स्त्रीः. Other nouns may have these forms (e.g. नदीम्, नदीः), but no other also has the forms allowed by 6.4.77 (स्त्रियम्, स्त्रियः).

July 18, 2013 / A

Restart 6.4

How easy to forget, how hard to remember. Currently at 6.4.60.

April 14, 2013 / A


Most of the available research on the Ashtadhyayi, whether from modern sources or from the tradition itself, is concerned with resolving conflicts between rules. That is, if multiple rules can apply equally to some situation, which rule should be applied? And what principles should we use when deciding which rule to apply?

The issues surrounding rule application are complex and difficult to analyze in a blog post. But here is a short example, courtesy of Joshi and Roodbergen (1987). Consider the derivation of the word प्रतीचः, which is in the case 2 plural. At some stage in the derivation we have प्रति + अच् + अस् and can apply one of two rules:

6.1.77 इको यण् अचि
Vowels in the इक् group change to semivowels when in front of vowels.
6.4.138 अचः
An अञ्चु (that is called भ and that has had its न् deleted) has its अ deleted as well.

For simplicity, let us call 6.1.77 A and 6.4.138 B. If A is applied first, we have *प्रत्य्चः as our final result. If B is applied first, we have प्रतीचः. To resolve this conflict between two rules, we should first apply the rule that takes away the cause (निमित्त) of the other rule. That is, if we apply A we can still apply B; but if we apply B, we can no longer apply A. Therefore B should be applied first. This gives us प्रतीचः, which is the correct result.

But I want to focus on a different sort of conflict-solving procedure. Some of the rules in the Ashtadhyayi are given a special “suspended” status; even when they apply, they are treated as if they didn’t apply. These rules are said to be असिद्ध (“unaccomplished”), and although most of the असिद्ध rules are in book 8, 6.4 remarks on them as well:

6.4.22 असिद्धवद् अत्राभात्
The rules from here to the end of 6.4.129 भस्य (and the rules under its scope) are treated as असिद्ध.

The device isn’t as complicated as it sounds. Essentially, it imposes an order on how rules can be applied: असिद्ध rules must apply last. One example of this device, courtesy of Rama Nath Sharma, is in the word शाधि, appears famously in the Bhagavad Gita:

शिष्यस् ते ऽहम् शाधि मां त्वां प्रपन्नम् ॥ २-७ ॥
I am your pupil. Teach me, your suppliant. (2.7)

The conflict starts from the state शास् + हि. These are the rules in conflict:

6.4.35 शा हौ
शास् becomes शा when followed by हि.
6.4.101 हुझल्भ्यो हेर् धिः
After हु and stems that end in a झल् consonant, हि becomes धि.

Again, let’s call 6.4.35 A and 6.4.101 B. Under the निमित्त device described above, A applies then prevents B. This results in the incorrect *शाहि. But both of these rules are treated as असिद्ध by 6.4.22. This means that although rule A produces शा + हि, rule B treats rule A as having not applied. This allows हि to change to धि and allows us to derive the correct form शाधि.

These are some of the issues at stake in 6.4. This chapter grows more interesting with each rule.