Defining Acts of Selection – Borer on Shabbos

Intention to Select

On Shabbos an action is only considered borer if one intends to perform an act of selection, eg to remove the bad fruits from a bowl. However, if one eg took out a fruit from a mixture to eat it and then discovered it was rotten, one may then put it to the side and this is not considered borer. (SSK 3:7)

Where one is cleaning an item that regularly becomes dirty of its dirt, this is merely considered an act of ‘cleaning’ and not ‘selection’ and is thus permissible even though they are attached. For example, one may wash plates of dirt or remove a louse from one’s clothes on Shabbos even if it is within the fabric of the garment. (SSK 3:fn7)

If a fly falls into one’s food or drink on Shabbos, one may not remove the fly by itself due to the concern that this is borer. However, one may remove it or tip it out with a little of the food or drink as then one is removing a mixture of the ‘desired’ and ‘undesired’ items, not the undesired item alone, alleviating the problem of borer.
SSK is only happy with removing a small quantity of the desired item in this case, as the fly is already somewhat distinct. However, with other types of mixture, one should only remove the undesired item with a significant quantity of the desired item, so that one would not consider what one is taking out from the mixture to be ‘waste’ from the mixture (MB 319:61, SSK 3:19, fn41, 5:fn24).

Where one is faced with a mixture that one wants to sort for non-immediate use, or from which one wants to remove the components one does not want, SSK raises the possibility that one can scatter the mixture such that its components are no longer considered mixed and then one may do as one wishes – there will no longer be any act of selection as there is no mixture. SSK is uncertain whether a person may scatter it for oneself to then choose from the scattered objects, or only whether one may do so for someone else. Rav Moshe Feinstein is lenient in this regard but Rav Elyashiv forbad this leniency entirely. One should consult with one’s Rav for guidance (SSK 3:fn6, Dirshu 319:15)

Where one has a mixture of fruit, cutlery, toys etc. one may not sort or separate this out into its component types for non-immediate use on Shabbos – this is also included under the prohibition of borer (even though one does not ‘desire’ one type over the other in this situation).
Similarly if one has loose pages that fell from a book and became mixed up, one may not sort through and put each page back in the correct place in the book unless one plans to read the pages immediately (SSK 3:83-85, 90-91).

When one has a mixture of cutlery, laundry, books etc which one wishes to sort into types on Shabbos, if one takes one item from the mixture at a time, without intending to select one type of item but rather taking whatever comes to one’s hand and one performs a useful action to this item, such as folding the laundry (in a manner which is not forbidden under the halachos of folding clothing, such as not along existing fold lines) or drying cutlery, it is considered as if one is taking the item for immediate use and it is permitted to then put each item down with other items of the same type (SSK 3:85, 88, 89, 15 fn150, PT 319:22, fn 174).