The Primary Melakha and Its Subcategories
As we discussed, techina (grinding; the melakha is known as tochen) is part of the process of turning grain into flour. In the Mishkan (Tabernacle), techina was performed to break down plant extracts into water-soluble granules, which would then be mixed with boiling water to create dyes for the Mishkan's coverings. The definition of tochen is breaking down one body into smaller homogenous components. The Rambam (7:5) defines this melakha in order to demonstrate the difference between a primary melakha (av; plural — avot) and its subcategory (tolada; plural — toladot):
The tolada is a melakha which is similar to an av among these avot. How so? One who minces a vegetable in order to cook it is liable, as this melakha is a tolada of techina, because one who grinds takes one body and divides into many bodies, and any action akin to this is a tolada of tochen. Similarly, taking a strip of metal and grinding it in order to use its filings — as goldsmiths do — is a tolada of tochen.
In other words, the av melakha of tochen is true tochen, turning a substance into tiny granules or a powder, while cutting up the substance into small pieces is a tolada of tochen.
The Maggid Mishneh ibid. (4) explains that only an action which is qualitatively equivalent to the primary melakha may be considered an av, but a melakha somewhat similar to the av is considered a tolada. He gives the example of the melakha of tochen:
Any melakha which is absolutely comparable to the av... is an av like it, but a melakha which is somewhat similar to it is called a tolada... for example, one who cuts up a vegetable. This is only similar to techina in terms of making many bodies from one body; because the techina changes the first body absolutely and cutting up [vegetables] does not, this is a tolada.
In other words, only actual techina, which changes the body of the substance, is an av, while splitting one body into many bodies is a tolada.
However, according to this, filing metal should be an av, because this is real techina, yet the Rambam writes that this is only a tolada! It may be that the definition of the av is preparing something for cooking through techina, and therefore filing metal, which is not designated for cooking, is not considered an av.
According to this, the definition of the av has two elements: a) true techina, and b) preparing for cooking. In the classic examples of tochen, there are two elements: in the Mishkan, the plant extracts were ground and then cooked (i.e., boiled in water); paralleling this, in the bread-making process, one grinds the wheat and ultimately bakes it. When only one of these two elements is present, this is a tolada of tochen.
Therefore, one who chops a vegetable in order to cook it is liable, because the first condition has been fulfilled here: preparing for cooking (naturally, the preparation must be specifically through chopping the food itself, not other general preparations). However, this is only the tolada, not the av, because the second condition has not been fulfilled, because one has not actually irrevocably altered a substance by splitting it into smaller pieces. Similarly, one who files metal is liable for tochen, since the second condition has been fulfilled, because there is actual techina here; nevertheless, it does not rise above the level of a tolada, since the first condition has not been fulfilled, because there is no preparation for cooking here. The same applies to someone who creates sawdust (Rambam 8:15).
While it is important to understand the theory of the melakha, there is no essential practical distinction between av and tolada, as both of them are Torah-level prohibitions.
How does one prepare a salad on Shabbat? May one chop vegetables into small pieces?
As we have seen, according to the Rambam, mincing vegetables is a Torah prohibition, a tolada of tochen. The source of this is in the Gemara (74b), in which Rav Pappa rules that one is liable for tochen for an action known as "parim silka" (or, on an alternative version: "paris silka"). What does this mean?
The Rambam understands that "parim silka" means mincing a vegetable known as silka (in Modern Hebrew, a selek is a beet), and this is what Rashi explains ibid.
On the other hand, Rabbeinu Chananel (ibid.) writes that "parim" is "like crushing, not like cutting," implying that only true techina is forbidden by the Torah, not mincing. The Rosh (7:5) explains similarly and declares:
I am astounded by Rashi's explanation of "parim silka" as mincing vegetables. When it comes to cutting up what one eats into small pieces, techina is not applicable at all!
According to him, mincing is not forbidden because of tochen. The Korban Netanel ibid. (10) explains his reasoning according to the view of the Rashba which we will cite later: the Torah does not require a person to eat food only in large pieces.
In fact, the Rambam's words appear to suggest that he also limits the prohibition to mincing. The Rambam (21:18) writes that "One who minces a vegetable in order to cook it — this is a tolada of tochen, for which one is liable." This implies that only if the mincing is in preparation for cooking is one liable, not if one cuts up vegetables in order to eat them in small pieces. A similar view is cited by the Ritva (74b) in the name of the Ri and the Ramban:
One who is paris silka is liable because of tochen — the Ri explains that this only applies in a case like this one, where one does not eat it raw. But with bread and the like which can be eaten immediately it is permissible, and so our master ruled in the name of his great master [the Ramban].
In other words, there is no prohibition to mince foods which are edible in their current form. The prohibition only applies to cutting up foods (like vegetables) which require cooking, in order to prepare them for cooking. This is also the view of the Remakh (Shevitat Asor 1:3, cited by the Kesef Mishneh, Shabbat 7:5).
However, the words of the Rashba in a responsum (Vol. IV, Ch. 75) indicate that any mincing should be forbidden because of tochen, even if the food is edible in its current form and there is no intention to cook it.
The Shulchan Arukh (321:12) rules in accordance with this view of the Rashba, that this is forbidden by the Torah: "One who minces vegetables is liable because of tochen." Note that he does not distinguish between vegetables which must be cooked and those eaten raw, even though many Rishonim (such as the Rambam and the Ritva) are lenient about this, and even though there are Rishonim (such as Rabbeinu Chananel and the Rosh) who are lenient when it comes to cutting vegetables generally. Indeed, the Arukh Ha-shulchan (321:7) is confounded by this ruling of the Shulchan Arukh, given that it is against the majority view in the Rishonim.
In light of this, even though the custom is to be stringent when it comes to mincing, nevertheless it is certainly less serious than true techina, since many Rishonim are lenient regarding this case. Therefore, one may mince food when there are additional reasons to be lenient, for example in a case where one is mincing vegetables in order to eat them right away, as we shall see shortly. (Similarly, there is a case to be made for leniency in the definition of "mincing," as we shall discuss below.)
Items Edible without Being Cut
There are those who understand that the Rema takes a more lenient view than the Shulchan Arukh on the issue of cutting up foods. In light of the words of the Shulchan Arukh, who forbids mincing absolutely, the Rema writes (ibid.): "The same applies to cut up dried figs or carobs before the elderly."
The concluding phrase of the Rema invites the following question: does the prohibition to cut up dried figs or carobs apply specifically when it is done "before the elderly?" The Magen Avraham (14) understands that this is indeed so: "It is implied that to do so before someone who can chew is allowed." In other words, this prohibition only applies to one preparing food for the elderly, because they are not able to chew the dried figs or carobs without cutting the fruit up first, but if this is done for a person who is able to chew these fruits without their being cut up, there is no element of tochen in this activity. The prohibition of tochen exists only with significant techina, which makes the food fit to eat, and thus it does not apply to items which can are edible in their current form, without techina.
The Bei'ur Halakha (ibid. s.v. Lifnei) argues with this assertion of the Magen Avraham:
In my humble opinion, his view is not self-evident, because [the Rema] inserts "before the elderly" because this is the normal way; [since] they are not able to eat if the fruit is not minced [it is normal to cut the fruit for them]. However, when it comes to items which grow in the ground, techina is applicable in any case, and thus it appears from the words of the Vilna Gaon in his commentary... Note, that even according to the view of the Magen Avraham, who allows one to chop food up before one who is able to chew it regardless, this is only true of dried figs and carobs, which one does not need to cut up; but when it comes to mincing vegetables and the like... it must be done for the current meal, even according to his view.
According to the Bei'ur Halakha, there is no distinction between things which can be eaten without techina and things which must be cut up before being eaten; the Rema simply cites a common example of a case where one would cut up carobs. Similarly, the Magen Avraham only allows, according to his view, cutting up carobs, because there is no great benefit in cutting them up for a person who can eat them as they are, but cutting the vegetable for a salad and the like is forbidden even according to the Magen Avraham, because this activity is significant, even for people who are capable of eating the vegetables in their whole state.
After the Fact
The Mishna Berura (ibid. 45) writes in the name of the Chayei Adam that one must be stringent, even about using vegetables that were already minced on Shabbat:
Mincing onions or radishes an hour or two before the meal is tantamount to incurring a liability to bring a sin-offering, and the onions must not be eaten.
However, one must point out that the Mishna Berura himself (318:2) writes elsewhere, in the name of the Peri Megadim, that in any case in which there a dispute among the halakhic authorities, the food is permitted after the fact. According to this, one should allow for the consumption of foods that were minced, since many Rishonim (Rambam, Ritva, Rosh, et al.), permit one to do so in the first place, as we have seen above. This is what the Livyat Chen (63) writes about the words of the Mishna Berura:
With all due respect, he has gone too far here, as the view of many Rishonim is to allow this in the first place... According to this, even though one who chops up onions an hour or more before the meal has certainly acted improperly, as he is acting leniently against the ruling of our master, the Shulchan Arukh... but in any case, after the fact one should not prohibit this food from being eaten on Shabbat.
Defining Chittukh Dak-Dak
What is the measure of chittukh dak-dak, mincing? The Yere'im (Ch. 274, 133b) writes that he is uncertain of the degree of fineness which would make one liable:
One must be careful not to crumble produce into small bits, but I do not known how to ascertain the measure of their fineness or granulation.
The Bei'ur Halakha (321:12, s.v. Ha-mechattekh) writes that indeed one is liable only for cutting food into tiny pieces, but when it comes to what is forbidden, one must be careful not to cut food into small pieces, even if they are not actually tiny.
A number of Acharonim have tried to define chittukh dak-dak. The Berit Olam (Tochen 20) writes that chittukh dak-dak is defined as the normal, weekday measure of fineness which people are accustomed to; therefore, on Shabbat, one should cut food into pieces larger than the norm. Rav S.Z. Auerbach (Minchat Shelomo 91:13; cited also in Shemirat Shabbat Ke-hilkhatah, Ch. 6, n. 5) proposes a more lenient approach:
The halakhic authorities have written that one who chops wood on Shabbat into small pieces is liable because of tochen... According to this, one must say that the reason that one is allowed to cut large fruits and vegetables on Shabbat into small pieces fit for immediate consumption is because one still needs to use one's teeth to grind them; this is different from chopping wood, in which the pieces are fit for their use immediately, without any [further] techina.
According to him, one must follow the function of the action. One who chops wood is liable even if the pieces of wood are still relatively large, since they are fit for use without any additional cutting. On the other hand, food that has been cut but must still be ground using one's teeth before being swallowed is still considered to be "unfit for its function," and thus the cutting is not considered chittukh dak-dak. According to this, chittukh dak-dak requires tiny pieces, almost to the level of techina.
In my humble opinion, it appears that the definition lies between these approaches: from many sources, it appears that tochen is the creation of a new identity. Every fruit has its own identity; every piece has its own identity. When one cuts a fruit into small pieces, the pieces lose their independent identity, and they become part of the general mixture of small pieces. According to this, it may be that the definition of chittukh dak-dak is that one cuts in such a way that it is difficult to recognize the identity of the piece. According to this, cutting vegetables into very small pieces for a salad will be considered chittukh dak-dak because it is difficult to differentiate between a small cube of cucumber and a small cube of green pepper, or between a small piece of tomato and a small piece of red pepper, etc. However, if a salad is composed of larger pieces, though they may be small, there is no issue of tochen in its preparation. Nevertheless, it is appropriate to prepare a salad proximate to the meal, so that there will be an additional mitigating element of immediate use, which we will discuss later.
Vegetable Slices and Sticks
In any case (even not for immediate consumption), it is permissible to cut vegetables into slices; there is no prohibition of tochen in this. This is what Rav Moshe Feinstein indicates in a responsum (Iggerot Moshe, OC, Vol. IV, Ch. 74, Tochen 3):
Does the prohibition of techina for vegetables apply only when one cuts them finely lengthwise and widthwise, like grinding flour; or does it apply even when one cuts only lengthwise or only widthwise, as one does with carrots, cucumbers and tomatoes?
Answer: In my humble opinion, it is obvious [that there is no prohibition of cutting food into slices]... Were it not so, there would be no limit to this, because it would be forbidden to slice bread into small pieces, unless we would employ the principle that there is no tochen after tochen; [similarly, it would be forbidden to cut] a large fruit such as an apple into three or four pieces. Thus, it is obvious that with foods, tochen is applicable only when mincing, as the Shuchan Arukh's language indicates about vegetables.
In other words, were we to forbid slicing food, the prohibition would make eating on Shabbat quite difficult, and it would be forbidden to slice bread because of tochen (were it not for the allowance of "tochen after tochen" which we will address later on). Therefore, slicing is not considered tochen at all. In light of this, Rav Feinstein allows one to cut carrots and cucumbers into sticks or spears. This same conclusion could be reached based on the view of Rav S.Z. Auerbach cited above: since people need to grind these sticks with their teeth, there is no issue of tochen in it.
However, it appears that one must differentiate practically between different levels of cutting. Cutting thin slices of vegetables is always permissible. However, when it comes to strips of vegetables, there is a distinction: julienning vegetables, i.e., cutting them into thin, narrow strips, such as those used in carrot salad, is clearly forbidden, since the strips are then mixed together and eaten as one piece (and this is the view of Rav Elyashiv, cited by the Orechot Shabbat, Ch. 5, n. 12); cutting thicker strips to be eaten individually — i.e., sticks or spears — should apparently be allowed, as this type of cutting is quite dissimilar to tochen. When these strips are made into a salad and are eaten in another way, there is a new creation, and every piece loses its independent identity; therefore, this is forbidden because of tochen. However when these strips are eaten in the same way as the whole vegetable itself is, it is logical that there is no problem in this, because the strips maintain their independent identity; they are merely smaller.
 Translator's note: The Rambam's term is chittukh me'at-me'at, which is equivalent to the chittukh dak or chittukh dak-dak mentioned by other authorities. We use the term "mince" for this type of cutting, as opposed to the term "chop", which we use for the regular chittukh of produce. This subcategory of tochen should not be confused with the primary melakha of mechattekh, cutting to size, which is the final step in manufacturing leather.
 The view of the Rambam in defining the av and toladot of tochen requires further study. I have chosen the understanding which seems most reasonable to me.
 However, it should be noted that the Rashba advances a different leniency, writing that grinding or cutting for immediate use is not included in the prohibition. We will deal with this later.
 It is also possible to enlist the view of those who regard mincing as a tolada. Even though generally we do not differentiate between the primary melakha and the subcategory, and an action which is defined as a tolada is forbidden by the Torah despite its differentiation from the av, it may be that when there is an additional alteration and the action is differentiated even further from the primary melakha, there is room to be lenient.
 However, this is determined based on the individual on whose behalf the food is being cut, not according to the general custom; thus, even if most people are able to eat carobs uncut, and cutting carobs for them is permissible, there is no allowance to cut them for the elderly who are unable to eat the carobs uncut.
 See Chut Shani (by Rav Karelitz, Vol. I, p. 102) who rejects the words of Rav S.Z. Auerbach: "The measure of fineness is not dependent at all on the question of whether, after mincing, one must still grind it by chewing with one's mouth at the time of eating. Techina is defined as anything which prepares it for eating (or for other purposes which one requires) by cutting it into small pieces, and if one prepares it for eating in the way which people eat it, in small pieces, this definitely falls under tochen." According to him, while it is true that the prohibition of tochen is applicable only if the substance is fit for its function, the function of the food right now is to be edible in the form of a salad and the like. The fact that the teeth will take a part in making this food fit for swallowing is immaterial at this time. See ibid. (pp. 100-102) that the prohibition of tochen is dependent, according to him, on the type of use: when a person cuts something in order to use it in a manner which is unique to small pieces — e.g., one wants to eat a vegetable salad, not each piece on its own — there is a prohibition of tochen; however, when the manner of use is identical, but it is easier to eat it in small pieces — e.g., one wants to eat apple slices and not a whole apple — there is no prohibition of tochen in this.
 However Rashi (74b, s.v. Chayav Achat Esrei) writes that one who cuts a reed into two or three parts in order to manufacture a wicker hive is liable for tochen; however, it makes sense that the level of cutting which is forbidden depends on the function and manner of use. This is what Rav Feinstein and Rav S.Z. Auerbach write in their abovementioned rulings.
 However, when a salad is composed of different vegetables, every vegetable piece maintains its independence as long as its source can be identified; only if it is not possible to identify the source is this considered the creation of a different identity, as we explained above. When discussing a salad composed of one type of vegetable or fruit, there is no significance to identifying the source of the pieces, and the criterion for losing identity will be the way it is eaten: are the pieces eaten together or each one individually?