Fungible (fŭnˈjə-bəl)

  • adj.
    Law Returnable or negotiable in kind or by substitution, as a quantity of grain for an equal amount of the same kind of grain.
  • adj.
  • n.
    Something that is exchangeable or substitutable. Often used in the plural.

If you want to properly understand attributions, you need to understand this concept thoroughly.

The mountain

Imagine if you will all of the swords ever made… this could apply as well to tosogu or paintings or sculptures or whatever you want. Baseball players… doesn’t matter. 

Pile them all up.

We want the good ones on top, and the bad ones on the bottom. 

What you will make is a mountain: one with a vast wide base and that narrows to a peak, surrounded by foothills.

If we think about baseball players, you will see Babe Ruth, Ted Williams, Hank Aaron… run through the Hall of Fame and they will be there at the pinnacle of the mountain. These are the heroes, the players who defined the game and have names that will echo down through history.

Just below the pinnacle, you have those that were great, nominated for the Hall of Fame but never quite made it. Jack Morris was a dominating pitcher for the Detroit Tigers in the 80s and helped them win the World Series, but he just didn’t get enough votes to make it. He exists in this area, just outside the gate, looking in. Fans of the team will remember his name, but others will soon forget.

Below this you have a huge number of pro players who played their position well, batted .272, didn’t help the team too much but also didn’t hurt the team. They may have played for many teams, and nobody can quite recall their names anymore, they were fairly generic. Roleplayers. Fungible. You are proceeding down past the halfway point of the slope now.

Below this you have journeyman players who got called up and sent back down to AAA ball. Never staying in the big leagues but never quite departing. Just warm bodies you can call on when someone is injured, before you trade for a better player to fill that role. As fungible as fungible can be. You are now at the wide base of the mountain.

Then there are the dreamers who will spend a career in the minors and never get out. Below that, those who cannot even stay in the minors. We don’t even talk about those guys unless there is a tragedy involved. You are now in the foothills around the mountain. If you get one of these guys on your beer league softball team you have a ringer, but they will never make any difference otherwise.

Standing far away from the foothills of the mountain: there be us. 

This mountain has a sharply defined peak and then gets wide very fast. There are so many more dreamers and journeymen in the foothills than there will ever be heroes at the peak of the mountain.

Keep that image in your mind, it applies to music, art, literature, sports, and so on. The greats are few, and distinct. The mediocre is frequent and fungible.


Nobody would ever say that Babe Ruth is an adequate replacement for Ted Williams. Nor is Ted Williams an adequate replacement for Babe Ruth. They are both heroes, but were different in how they went about being heroes. 

Let’s change mode: Mozart is not a replacement for Beethoven and vice versa. Both musical geniuses of the highest caliber, yet completely distinguishable from each other. You may like one more than the other but nobody can contest their genius or even say one is of higher order than another (well, you can say it, but you can also expect and understand arguments against your position). 

Change mode: Rembrandt and Leonardo da Vinci. 

Change mode: Messi and Pelé.

Change mode: Ferrari and McLaren

Heroes are distinct. Heroes stand in the sun and cast a shadow, and everything else exists within that shadow. There are multiple heroes but there are not infinite numbers of them: the peak of the mountain is limited in space and only rarely does someone come along who can climb to the top of the mountain, then make a platform on which they will stand. When it happens, you have a truly generational talent that may never come again. 

Tom Brady. Wayne Gretzky. Van Gogh. Michelangelo. 

Among heroic peers those few, rare ones, raise their hand and touch the stars.

This however is not the center topic of our conversation. We need to first glimpse the peak before going where we are going.

Down. Then back up.


The journeyman ballplayer who gets called up for a weekend and sent back down after a trade, he is truly fungible. Another term for this used sometimes is warm body. There is nothing about such an individual that distinguishes him from his peers. He is there to just do the job as best as can be done at short notice. The fact that he is one interchangeable part in a sea of millions is what makes him chosen. The fact that he is means he is available and within reach and can be discarded after his job is done.

If I make a painting, I can tell you right now I will like it and my Mom will like it and maybe someone who doesn’t know anything about art will like it… but it is not something that you also would not be able to produce with about 10 minutes of observation of my “techniques.”

There will be no way for an external observer to determine, after the fact, whether you made that painting or whether I made that painting.

There is no special style. 

There is no special training.

There is no special technique. 

There are no special materials.

Most importantly: there is no refinement. To sit far away from the mountain and view it all is the place of a hobbyist. Go to the store, buy some paint, slap the paint on something, and you’re done. The results are interchangeable with anyone when you are dealing with the pool of painters who are not trained, have no technique, and are just painting from first principles for fun.

Every now and then you may stumble into a natural wizard, but every now and then you win the lottery too. For the most part, no training, no technique, no clear vision or commentary = fungible results.

Where this applies to the land of attribution is as follows.

The judges, they know nothing!

This is the first statement that comes to mind when a collector submits an item and receives a judgment he does not like. Of course if he likes the judgment then he salutes the wisdom and clear vision of the judges. His opinion of the judges basically goes along the lines of how well they reward him and correspond to his viewpoint, rather than how accurately they make judgments according to an objective viewpoint. 

I have experienced it myself, and no doubt you have. 

The trick is to be aware of this thought and try to control it. Because always, you might be missing something and there may be something to learn from a judgment you don’t agree with. 

Anyway, a different source of this response is when a collector submits a piece to two different judges or institutions and receives two different attributions.

Well, obviously one of them doesn’t know what they’re doing. 

You can reliably bet that the collector’s ire will be focused on the organization who gives the lower of the two attributions. He would prefer if they both traced the thread back to the same (ahem, higher) attribution. When it doesn’t happen it causes distress and a breakdown of faith in the results. If the two answers are not in the same ballpark, he should indeed be bothered by this.

However if they are equal answers in terms of skill and time period, there is no disagreement in the judgment though they name different makers if skill is not at the peak. If we go back to the mountain and consider the journeymen and the fungibility of them, this is directly associated with two institutions coming up with different answers. The foothills are a wide and low area and determining any particular location within there is difficult. The only significant aspect of such a judgment is that it is within the foothills.


Any two low ranking schools, by definition, do not have high skills. Those high skills are required to make items which lift their heads out of obscurity. Lacking that skill, you get obscurity.

A low ranking school has such a reputation because the blades they made were mediocre. The whole thing by definition prevents high quality items from being attributed back to low ranking schools.

When you are messing around in the mud trying to take a blade with no particular special features and assign it to a maker, the only distinguishing feature of this item is that it has no distinguishing features. It is one of these fungible items, a faceless journeyman role player. The judge then is forced to try to assign a time period to it, and then find a school or individual associated with faceless journeyman quality and assign this piece to that maker.

As such, one answer is going to be as good as another.

When a westerner hears Bungo Takada from one judge and Mino Kanefusa from another judge, he thinks these guys are clueless because they can’t agree on a maker. The problem though is in the collector’s head for not recognizing that:

  • the skill shown in this item is mediocre grade
  • the item has no particular distinguishing features
  • the answers are meant to illustrate the most probable candidate and
  • all candidates are equal probability at the base of the mountain

Thust at the base of the mountain, as long as you recognize that item belongs at the base of the mountain, you get this result that any two answers tend to fungibility.

[Note: I am going to pull some excerpts from a conversation between NBTHK officials taken from the English Token Bijutsu magazine in order to illustrate some points along the way.]

Yagi : Aren’t there also those among unsigned blades acceptable by the new Shinsa criteria (i.e. Hozon/Tokubetsu Hozon) yet requiring re-doing of the Kiwame or attribution because the old attribution is considered inappropriate?

Tanobe : It could certainly happen.

Yagi : I hear there are quite a few like that. Doesn’t it create some problem when a sword is submitted to the Shinsa repeatedly in terms of accepting it with the old Kiwame?

Tanobe: Having to give a different Kiwame does happen because the Shinsa is conducted by human being. However, I don’t think it would cause any trouble if the age of production in addition to the competency ranking of the maker remains the same. For example, Taira-Takada’s Kiwame can most reasonably be converted to Kanefusa’s.

Judges are very comfortable with this fungibility between mediocre level makers. Collectors need to understand this and be able to do the same mental mathematics.

Nobuo Ogasawara in Selected Fine Japanese Swords from European Collections writes some very practical advice. He says in there (at some point, again paraphrasing), “there is no disagreement in the judgment of appraisers who may appraise a sword to Bungo, Ko-Mihara, Uda, etc.” …

That is really badly paraphrased but he was making the point that the third and fourth tier koto schools are somewhat fungible and if two appraisers give you different answers within this set, they are not in disagreement.

— Darcy Brockbank 

Yes, I quoted myself.

The take home from a low level attribution, is simply that it is low level work of a certain time period with a small nod toward some school or maker as a likely culprit. You are free to form your own opinion that differs within reason from this, and it can indeed be arguable, but at the same time you need to realize that in most of these cases there is no firm conclusion that can be made from the work that is displayed.

That is, many answers can substitute for the right answer, and the real right answer can only be known with a time machine. Thus, all we have is basically a group of somewhat equivalent right answers and arguing between them doesn’t have a lot of meaning. As long as the candidate answers generally match for time period and skill level, they are all equivalent. Fungible.

The dreaded generic answer

This leads us to another complaint.

 I submitted my Higo tsuba for papers and it came back Higo. I am so frustrated.


I submitted my Goto menuki and they came back as Goto. I knew they were Goto already! They obviously don’t know what they’re doing or else they’d tell me which Goto made them.

What’s happening here is again the problem of fungibility but it is at a bit of a higher level of skill. In this case you have collectors who indeed have good eyes and know what they are handling and want more specific information. So they go to the judges and the judges just confirm what appears to be obvious on its face. 

The issue is that there is no additional information inherent in that object that can lead to a more exacting judgment. You know it’s Higo, I know it’s Higo, the judges know it’s Higo, everyone knows it’s Higo because that part is obvious. Past that, on this piece, we run out of clues. The collector is hoping the judges see something that he missed, but in reality, the collector didn’t miss anything. It has the whole story on its face. So a good judge will only judge so far as he can stick his neck out. If the item says no more than Higo, the judge says this without editorializing an opinion out of thin air.

In some cases in the past judges did stick their neck out more and sway to an individual, especially with Goto works but this has lead to some attributions being a bit weak. They did this because of pressure from collectors, such as the emotions expressed in the above two examples. These days it is becoming more rare for judges to do this because it starts building a problem of too many attributions for certain individuals. 

If a piece comes back just as Goto or as Higo, it means that it is fine quality work that has reached above the level of mediocrity and distinguished itself, but, there are still no fingerprints that let us reliably nail the culprit responsible for making it. Maybe in the future… but not now. So you get a conservative judgment. This is much better for you, and for everyone, than a liberal judgment that assumes too much and is as a result, not reliable though more emotionally satisfying.

I would instead say to people who get this kind of judgment, that does not extend past what they already decided for themselves, is: you should pat yourself on the back. Because you already answered it as far as it is possible to go within the limits of human knowledge. Good job!

At the top

Fungibility applies to some degree at the top as well. Between top level smiths who are trained in the same school there exists a degree of overlap. It is not necessarily because a hero level smith like Masamune is himself exchangeable for Sadamune… however both of them can hit a home run. Like Ted Williams and Babe Ruth can. 

What we have to do with attributions is look at the home run and then determine who hit that ball, and this is a difficult process. As such the judgment has some fungibility to it due to some overlap in style, time period, and skillsets.

Ultimately then fungibility itself is a property that is at its maximum at the lowest skill levels and then fades out as skill increases. As such, as the level of the attribution increases (i.e. to higher ranked smiths) we expect that the attribution gains in accuracy and reliability. We expect a low level attribution to only be accurate in time period and in skill level.

It’s very rare to have any judgment that would receive universal acclaim, but it is more likely that one judge out on a branch all by himself with a distinct answer not within the zone of fungibility with all other known experts, is going to be in fragile territory.


Nobukuni is said to be the student of Sadamune. Whether he is or isn’t, is again a time machine problem to solve. But, one of the reasons this is said is because there is overlap in the style and skill levels between these smiths. While Sadamune is absolutely the higher level smith, Nobukuni shows very fine skill and when grading out with condition you can end up with a piece that is difficult to determine between the two smiths. With some technical and skill overlap one must then give some breathing room between judges who might on the one hand say, Nobukuni’s finest masterwork quality and a great sword, but a little substandard for Sadamune. They are saying the same thing, and placing that blade into the overlap area between the smiths and just describing the exact same thing from two different perspectives.

Knowing when this applies is a matter of reading and study and direct consideration of real world examples.

Consider Rai Kunitoshi, the work early in his career is labelled as Niji Kunitoshi for the fact that it doesn’t include the word Rai in the signature of the signed examples. The style of those blades are very close to Rai Kuniyuki and the two smiths are of identical skill. So, we can expect that there is a bit of fungibility between the attributions. At the later period of Rai Kunitoshi’s work, Rai Kunimitsu was making daimei and probably daisaku for him. The school was large, rich and famous and probably had more orders than they can fill. As such, for that final style there is some fungibility between Rai Kunitoshi and Rai Kunimitsu. 

Both answers may be equally acceptable, or both acceptable and one slightly more acceptable. Answering differently does not imply cluelessness on the part of the judges, but understanding why they might be answered differently implies sophistication on the part of the student. 

That said, there should be less fungibility between Rai Kunimitsu and Rai Kuniyuki. Much time has passed between the smiths and the style has radically evolved. So, that should be a real argument between the two smiths when it is concerned and one that has a right answer and a wrong answer. 

Fungibility can have a gradient

In the example above, there is no real daylight between the skill levels of Rai Kunitoshi, Rai Kuniyuki and Rai Kunimitsu. There are style and period changes, but the skill doesn’t really increase or decrease between these makers. As such there is no direction to the fungibility.

If you were to be looking at a mumei blade that you feel is Rai Kunitoshi, now you need to consider some additional dimensions. 

This is actually something that needs three dimensions to illustrate because of overlaps in time and skill, but this kind of gives an idea.

Given Rai Kunitoshi in the middle, there are multiple ways you can go from here. You can go to higher skilled groups like Awataguchi or sideways to other individual smiths considering time as a limitation. You can go down in skill to Enju or Ko-Mihara. The further away you move in time and skill level, then the less reasonable it is for two answers to be considered equivalent and acceptable.

Because we are dealing with a higher skill level, we do not have the option of a large pool of equivalent answers. We have a near pool of possibly equivalent answers, but only in one direction, having factored in style and quality.

To go to Awataguchi it would have to look quite old as Rai Kunitoshi and show absolute top line skill within the body of work. To go to Ko-Mihara it would have to be on the younger side and show more mediocrity. There is no such thing as a poor quality Rai Kunitoshi however. So there are limits. If the skill level is very poor then Rai Kunitoshi shouldn’t have been an appropriate answer at all in the first place.

For any individual smith or school there is a mapping that looks like this, where there will be overlapping answers that are also sound. In some cases, the answers can be equally likely, and in some cases not so likely. 

If for example we were sure we had a Rai blade and couldn’t decide between any of the smiths then we should end the attribution at Rai as all answers are equally likely. In practice though it shouldn’t happen that Rai Kuniyuki and Rai Kunimitsu would both be equivalently likely answers on a Rai Kunitoshi because they represent different styles that do not overlap each other, though they overlap Rai Kunitoshi. So we don’t end up with Den Rai as a good answer for a paper, though it may be all you might be able to answer for kantei.

If we felt though it was about 75% chance Rai Kunitoshi and 25% chance Rai Kunimitsu, then we’d answer probably DEN Rai Kunitoshi and allow a degree of interpretation in the answer as this is one of the uses of DEN. If we felt 100% Rai Kunitoshi then we’d just answer Rai Kunitoshi. 

How you get to that 100% can often be via the conclusion that there just is no other appropriate answer. Method of elimination does work. 

Fungibility scope changes with skill

The primary difference here is that when it comes to low skill, all answers end up being equivalent as long as the answer is the right time period and the right skill level being proposed. 

With high level work, the fungibility is much more limited because high level work gives us more significant features to seize on when making an attribution.

Low level work is a greased slide and down you go to the bottom, all in a heap. High level work is a cliff face with plenty of handholds and toe holds presenting a skilled climber a reasonable route to the top.

When fungibility presents itself on high level work, it tends to fit these models:

  1. Two answers are possible due to overlap, with one somewhat better than the other: the best answer is then chosen, the second left as an expression of commentary and alternate thinking, and sometimes DEN is used to express the leeway on the attribution.
  2. Several related answers are possible: this leads to a school attribution.
  3. The case of several schools being possible indicates a very murky assessment of skill, so this shouldn’t generally be arrived at by a qualified judge (never say never though). In reaching this case though, the lower skilled school in this case is going to be the most correct answer and DEN possibly attached.


When you are dealing with smiths of a similar skill level, style matters as much as time period. Masamune is considered peerless, however the fact of the matter is that the best work of Yukimitsu, Sadamune, Go Yoshihiro, Norishige and Shizu, can all provoke arguments in terms of assessment to Masamune or not.

With these smiths, they all overlap somewhat in skill but in style, they mostly come in pairs: Go and Norishige, Yukimitsu and Sadamune, and then Shizu matches with Masamune best.

So when you are looking at a Masamune that holds some doubt, you need to assess the skill and the style and then follow your nose. Again it is something that exists in three dimensions and consider this two dimensional representation an approximation.

What I’m trying to illustrate here is that there is a core of undoubtably Masamune within a larger shell of most-probably-Masamune (the fungibility zone). His style overlaps and the age overlaps with these five satellite smiths, related by school. But the attribution can only be made to Masamune with certainty inside the center region and the strongest overlap is with Shizu. Shizu is the right target for a blade that is “so Masamune like it is almost Masamune but not quite Masamune.” A hidden dimension on this 2D chart is skill but all of these smiths also overlap on skill.

As you expand outwards from that certain core you get more overlap where an attribution to Masamune may still be possible but the doubt increases and other possibilities also arise as decent answers.

Continue to move and the probabilities change: the alternatives are more likely and Masamune becomes a side thought.

Even further away along any dimension, eventually you get to a spot where Masamune is no longer even a plausible answer and the only answer is one of these satellite smiths.

I am not so happy with the 2D expression, as this flat representation makes it appear that those smiths are more active than Masamune and they are not. But VR is still beyond the reach of my blog. The fungibility zone also should be considered to get weaker the further from the core, but no radial gradient is available to me in my toolset to make this chart. Don’t take the relative size of the ovals to mean much either. I’m just trying to establish some relationships and similarities.

What Masamune achieves that the others do not is a balance between a vibrant direction coming from Ko-Hoki and Ko-Bizen (and where a Shizu or Norishige might be simply outrageous in terms of its activities) and the elegance and control inherited through the Yamashiro style. So, his work shows magnificent vibrancy but it is never out of control. We can use terms such as restraint and wildness to indicate this as well but none of them are particularly better than the others.

Yukimitsu and Sadamune usually fall more into the quiet side of things, where elegance and control are become dominant over wildness and vibrancy. 

When you consider a work then of Masamune that shows some doubt on the attribution, you can assess the style and age and come to understand the mind of the judge. If it becomes more restrained than normal, you should be thinking of Yukimitsu and Sadamune. If it looks a bit younger than normal then you should eliminate Yukimitsu and go to Sadamune.

If the work is wild but more out of control and a bit younger, you would head to Shizu. If it is wild but more coarsely made, you head to Norishige. The work of Go is hard to assess in 2 dimensions because it can be equal or a bit more quiet than Masamune in wildness, but it can also feature a more exaggerated hamon and similarity in jihada to Norishige. Without extra dimensions to distort the chart into, I had to cut corners in the placement of Go. His style is overall more like Norishige and Shizu than Yukimitsu and Sadamune, though he tends to have a more controlled expression than Norishige or Shizu. So, I did my best but it is still lacking.

When looking at this diagram then we should take home a message that Norishige and Yukimitsu are not fungible though they are somewhat with Masamune. 

A Yukimitsu that has some questions about the judgment but the skill is extreme, you can see you should be thinking Masamune or Sadamune. A Norishige that has some questions about the judgment but the skill is extreme, you should be thinking Masamune or Go. A Shizu that has questions about the judgment but the skill is extreme, you think to Masamune.

And going back to Masamune, as you retreat from the top level of skill you follow the style and age to the right conclusion.

If none of these smiths is the right place or even in the right direction from Masamune then the original attribution to Masamune would likely be extremely misplaced. 

This is a paradigm and though you may never handle a Masamune or own one (most people never will), the paradigm is a tool you can use to understand other judgments. 


What I want to illustrate with this is that judgments have some leeway and judges that dissent in their conclusion are not necessarily dissenting in their thinking nor should they be separated into a camp of idiots and a camp of geniuses.

They are simply aiming for a most correct approach, not finding the only absolute answer because any reasonable person needs to admit that this is not possible without a time machine. 

Though I discussed specific examples here, it’s important to note that it applies much farther than just these cases.

Low level attributions remain fungible and do not disagree, if the time axis and skill axis agree. This is the best way to read an attribution to a low level maker or school.

Higher level attributions have a direction or gradient to them that can be understood and explained by the difficulty of judgment and that top smiths and schools in practice have closer skill levels and more overlapping work styles than the market would otherwise expect. The mind of the judge will lie within the commentary, and while not always completely spelled out, the pieces will be there for you to assemble the thought process.

Suzuki: One could buy a Sadamune sword [i.e. with Tokubetsu Kicho green papers] and only learn after the NBTHK Shinsa [i.e. resubmission to Hozon] that it was actually Nobukuni.

It is hard to be specific here, but it seems to depend on what the blade actually looks like and how flexible we can apply the standard of acceptability [i.e. of the existing judgment].

For example, we all know that Ko-Hoki and Ko-Bizen blades look very much alike, and the attribution (Kiwame) could readily be convertible. People wonder how we could get mixed up with swords made by different schools. Even from our professional viewpoint, the workmanships of those two schools are very similar, yet have to be differentiated [somehow].