- Question: [Thursday, 7th Tammuz 5781]
Is it permitted to play with a Rubik cube on Shabbos or does it involve borer or another prohibition?
It is permitted to play with a Rubik’s cube on Shabbos to set up the various sides with a single solid color, and doing so does not involve any prohibition. If, however, a piece of the cube comes out it is forbidden to reinserted on Shabbos due to the prohibition of Tikkun Keli.
Explanation: The Borer prohibition only applies when one separates one item from another, and since here the items do not become separated at all and rather always remain as a single cube therefore it is not relevant to the Borer prohibition. Furthermore, it is permitted to select that which one desires for right away use, and when one is playing with the cube, the moving of the pieces is considered for right away use. It likewise does not contain a writing prohibition, being that it is not considered a real picture, and in any event the picture already exists and simply needs to be arranged, and is hence no different than a puzzle. Now, while there are some Rabbanim who argue on the merits of the above points, I believe the main consensus amongst Rabbanim and Milkatei Halachos is to permit it due to the above reasons and so is my personal opinion. To note, that some of these Rabbanim [i.e. Rav Farkash] make no mention of some of the arguments to permit using it, and based their opinion on a separate ruling of Rav SZ”A, when in truth it has now become publicized that his opinion was to permit playing with the Rubik cube. Accordingly, perhaps even they would agree today after all the above information that it is permitted.
Sources: See in length Koveitz Beis Ahron Veyisrael 185 p. 148-153; Poskim who permit: Shulchan Shlomo 3 340 footnote 28 that so ruled Rav SZ”A; SSH”K 16:25; Piskeiy Teshuvos 340 footnote 179; Gam Ani Odecha 1:33; Koveitz Beis Ahron Veyisrael ibid; Poskim who prohibit: Shabbos Kehalacha 12:123 footnote 232; Shvus Yitzchak in name of Harav Elyashiv; See regarding moving within the same mixture: Siddur Admur regarding blowing the fly to the edge of the cup; P”M 319 A”A 14; Poskim ibid