Choosing Words with Care: Kukai's 'Shoji Jissogi' and the Practice of Language That Reaches the Heart

Words Are Not Signs—They Are Reality Itself

Late in his life, Kukai composed a work titled *Shoji Jissogi*. Translated plainly, the title means "sound and letter express *jisso*—things as they truly are." In that text, Kukai treated language not as a mere sign that carries meaning, but as the very truth of the universe appearing in phenomenal form.

This differs sharply from the modern view of language. We tend to handle words as "tools that carry thought." Kukai's view is more active: the moment a word is spoken, the vibration of its sound and the motion of its meaning together raise a new piece of reality in the world.

When you say "good morning" to family in the morning, for example, it is not a sign-sticker for a greeting. That one phrase adds a certain temperature to the other person's first hour of the day, and lights a small flame in your own mouth and heart as well. In Kukai's view, speech is always the act of *producing reality right here, right now*.

The Mystery of Speech in Shingon

In Kukai's esoteric Buddhism, among the three mysteries of body, speech, and mind, *kumitsu*—the mystery of speech—stands as an independent domain of practice. Chanting a mantra is central to Shingon practice precisely because words themselves are considered to hold the power to call forth the world of the Buddha.

A mantra is not like an ordinary sutra. It is not primarily meant to be understood and savored for content; rather, the vibration of its sound functions as a key that resonates with the universe. By repeating specific sequences of sounds—such as the Komyo Shingon or the mantra of Dainichi Nyorai—the practitioner opens a circuit connecting their body to the world of the Buddha.

This feeling that "power resides in sound" applies to daily language as well. "Thank you" spoken casually and "thank you" spoken from the heart differ entirely in both acoustic vibration and emotional warmth reaching the other person. Viewed through the lens of *kumitsu*, every single conversation of the day becomes a miniature mantra practice.

Neuroscience Echoes the Idea That "Words Make the Self"

Contemporary neuroscience offers striking support for Kukai's view of language. Research led by Dr. Andrew Newberg at the University of Pennsylvania has shown that the prefrontal circuits of people who habitually use positive language work differently from those who rely on negative language. People who routinely say "thank you," "that helped," and "because of you" show reduced stress hormones and greater ease building cooperative relationships with others.

This is not superficial "just think positive" advice. The brain receives words you have spoken as *information about yourself* and gradually rewires its neural circuits in response. In other words, the words you speak slowly—indirectly—shape the very form of your own mind.

The thesis of *Shoji Jissogi* that "sound and letter raise reality" has, twelve hundred years later, been rediscovered in the vocabulary of neuroscience.

Three Daily Practices for Words

Bringing Kukai's view of language into everyday life requires no grand training. Begin with three simple practices.

Practice 1: Don't speak the "un-words."

Try choosing one day a week when, consciously, you do not use negation words like "impossible," "can't," "pointless," "worst." At first you may be startled by how habitually such words appear. Replacing them with "I'll try," "I can move one step," "there's learning here," or "I can rework this" subtly shifts where you are standing in the same situation.

Practice 2: Don't enlarge the subject.

Phrases like "everyone is saying," "people generally think," or "anyone would feel" dissolve your own voice into a crowd—and push the listener into that crowd too. Just returning the subject to yourself—"I felt," "from where I stand, it looks like"—changes the texture of the conversation. In *Hizo Hoyaku*, Kukai taught that truth appears only through each individual body and mind. Returning the subject to yourself is that very teaching, enacted at the level of language.

Practice 3: Insert one beat before sending.

With messaging, email, and social media, make it a rule not to press send immediately after writing. Once the message is finished, lift your eyes from the screen, take one breath, reread it, and then send. Those few seconds dramatically raise the probability of catching a sharp word written in momentum or an unnecessary sentence that slipped in. In Kukai's time, letters took days to reach the recipient, and there was natural space to rewrite. Precisely because we live in an era of instant transmission, this "one beat of space" becomes vital.

Small Techniques for Raising the Temperature of Words

The same content carries very different warmth depending on how it is said. Here are a few small techniques.

Change "please do X" into "it would help me if you could do X."

Moving from command-form to request-form dramatically changes how the other person receives it.

Convert negative forms into positive forms.

Instead of "don't be late," say "it would make me happy if you came on time." The request is the same, but the direction in which the words land in the other's heart is not.

Use the person's name.

Including the other person's name just once in a conversation deepens how the words land by a measurable notch. This is an effect verified in psychology—the emotional region of the brain activates when we hear our own name spoken.

One evening, stuck on a work problem, I asked a family member, "Do you have a minute to talk?" They replied not with "sure, what's up" but with "of course, I'm listening." The meaning is almost identical, but that single word "of course" visibly released the tightness from my shoulders. How we choose words may look like a small difference, but it arrives as a clear difference in temperature to the one receiving it. This is the small thing I was reminded of that night.

Silence Is Also Language

Kukai's teaching contains a wisdom about *not* speaking equal to its wisdom about speaking. In *Goyuigo*, he repeatedly stressed to his disciples the importance of restraining the mouth and not piling up words. As noted earlier, four of the Ten Good Precepts concern speech.

We now live in an era where everyone is a publisher through social media. This also means it is an era in which a thoughtlessly emitted word easily wounds both oneself and others. The wisdom of "not saying" has become as important as the wisdom of "choosing what to say."

Silence is not avoidance. Sometimes it holds more meaning than words. The silence of listening without cutting someone off. The silence of letting your own anger sleep overnight before responding. The silence of not rushing to a conclusion. All of these are part of the practice of the mystery of speech that Kukai pointed to.

Start with the First Word of the Day

Trying to control every word of the day is unsustainable. Instead, consider treating only the first word of each morning as sacred.

The first word out of your mouth after waking. The first greeting exchanged with family. The first sentence spoken at work. The quality of this first utterance quietly sets the tone for every conversation that follows.

Saying "good morning" a touch more clearly. Consciously saying "thank you" once during the day. Opening a meeting with "thank you for today, looking forward to working with you" while making eye contact. Tiny things—but continued, they lift the temperature of the human relationships around you in ways you may not directly notice.

Language Is Your Last Thread to the World

At the closing of *Hannya Shingyo Hiken*, Kukai wrote that the teaching of language is "a lamp that illuminates the darkness within one's own mind." Precisely now, awash in information online, it is worth remembering that each single word you choose is the final thin thread that connects you to yourself and to the world.

You do not need flashy vocabulary. You do not need to expand your lexicon. What matters is taking the utterly ordinary words you already use every day and reselecting them with just a bit more care. Doing that alone, the same daily life begins to carry a different texture.

Tomorrow, try making the first word you exchange with someone a little more careful. That one word adds a small warmth to the other person's day and to your own. What Kukai pointed to twelve hundred years ago in *Shoji Jissogi* is, in the end, this quietly obvious and quietly profound truth: the accumulation of such daily words is what weaves a life into its own shape.