Two days ago I got my first Rubik's cube. Yesterday I solved it blindfold.
Toby Sharp
22nd December 2003
A few weeks ago I was watching TV when a guy came on to this show about world records, and solved the cube while blindfolded. I was blown away by this and thought, I have to learn that trick.
I didn't have a cube, and hadn't played with one for 20 years - not since I was a kid. I had certainly never heard of someone solving it blindfolded.
After a quick visit to Google, I discovered that the guy I'd seen was Ralf Laue. I also found some helpful tips and guidelines on how to solve the cube blindfold. The most useful of these was a document by Richard Carr.
At about this time, my wife Donna asked me what I wanted for my birthday and I said I would like a Rubik's cube. (Donna is fantastic and it's not quite clear why she puts up with a geek like me.) Afterwards I realized that now I couldn't go and get a cube; I would have to wait for my birthday which was a couple of weeks away.
After reading about Richard's blindfold cubing system, I realized that most of the learning would be mental preparation: learning the moves I needed, being able to store and manipulate a mental map of the cube. So I set myself the challenge of learning to cube blindfold without having a cube. My target was that as soon as I got the cube, I would solve it blindfold.
I learnt Richard Carr's system, with some variations of my own. Some of his moves I have exchanged for moves I discovered from playing with the Cube Explorer program. For example, for corner orientation, I learnt [U2 F L' D2 L F'][U2 F L' D2 L F'] which turns corner UFR clockwise and corner UBL anti-clockwise. This was easy to remember, as was the inverse. For edge orientation, I learnt [F U2 F2 D' U' L' U L D F2 U' F' U'], which changes the orientation of edges UF and UR.
For memorizing the cube, I use a mnemonic system with which I was already familiar. This is the phonic system used by many memory experts and performers. In this system, each number is associated with a particular phoneme, and words are constructed from the phonemes. The words are chained together in a visualized story, and this is far easier to remember than the original numbers.
When I had a spare evening, I would learn some more of the process. I learnt corner permutation one night, edge orientation another, etc. I printed out some random cubes from Cube Explorer for practice and devised my own mental exercises. I would memorize the state of the cube and work through solving the cube mentally. At each stage, I worked out which moves I was going to make, then updated my mental picture of the cube, then I (pretended to) make the moves I had planned.
Two days ago I had my 30th birthday. I won't pretend that I went straight into a blindfold, because actually I was having a pleasant time with my family. I'm not quite that pathetic. In the afternoon I had a go at the blindfold task.
I hadn't made these moves on a cube before; my preparation had been entirely mental. I found that physically turning the faces of the cube was a different experience than just mentally playing the moves out. Also the cube was rather stiff and seemed to stick at times.
I recall that the state of the cube was: corner orientation 2 0 1 1 2 0 2 1, edge orientation 1 0 1 1 1 1 0 1 0 0 1 1, corner permutation 7 3 1 8 4 5 6 2, edge permutation 10 4 8 3 11 6 2 9 12 1 7 5. (The memory system I use allows me to retain this for quite a while.)
Sadly the first attempt went wrong. When I played back some of the moves I had learnt without a blindfold, I realized that I had learnt the edge orientation move described above incorrectly. (I had been omitting the B' U' steps.)
I didn't attempt the cube again that day as I was somewhat busy having a surprise party which was one of the happiest moments of my life :-)
On the next day, I had another attempt in the evening when my kids were in bed. The state of this cube was: corner orientation 2 2 1 0 1 1 2 0, edge orientation 1 0 1 1 1 0 0 1 0 0 0 1, corner permutation 2 7 6 3 1 5 4 8, edge permutation 2 6 11 1 3 7 9 10 12 8 4 5.
I proceeded as follows. First, corner orientation. Orient pairs (1, 3), (2, 5), (6, 7). Second, edge orientation. Orient pairs (1, 3), (4, 12), (5, 8).
At this stage, Donna asked me to help my nephew Liam with his Lego building. She took the cube and put it out of sight before I removed the blindfold. Then I helped Liam with the Lego dinosaur and returned to my position. On went the blindfold, and then I received the cube back. (I didn't see the cube at all during this diversion.)
Next, corner permutation. Corner 8 is already in place. To position corner 7, B2 then cycle UFL > UBL > UFR then B2, leaving 4 2 6 3 1 5 7 8. To position corner 6, do F2, cycle UBR > UFR > UFL and F2, leaving 4 2 1 3 5 6 7 8. Now cycle UBR > UFR > UBL leaving 1 2 3 4 5 6 7 8.
Lastly, edge permutation. I find this the hardest part as there is much to remember. It took me a long time between moves figuring out what to do, and what state it would leave the cube in. Get edge 11 into middle layer by cycling UR > BR > DR, leaving 2 6 9 1 3 7 4 10 12 8 11 5. Get edge 10 into middle layer by cycling DL > BL > UL, leaving 2 6 9 5 3 7 4 1 12 8 11 10. Get edge 9 into middle layer by doing F2, cycling UL > FL > DL then F2 leaving 2 6 1 5 3 7 4 8 12 9 11 10. Swap edge pairs (9, 10) and (3, 4) leaving 2 6 5 1 3 7 4 8 9 12 11 10. Swap edge pairs (10, 12) and (1, 2) leaving 6 2 5 1 3 7 4 1 8 9 10 11 12. Now it gets slightly easier because the middle layer is done. Swap edge pairs (1, 5) and (3, 7) leaving 3 2 4 1 6 7 5 8 9 10 11 12. Cycle DR > DF > DB leaving 3 2 4 1 5 6 7 8 9 10 11 12. Finally, cycle UL > UF > UR leaving 1 2 3 4 5 6 7 8 9 10 11 12.
When I took off the blindfold, the cube was solved! Hooray! It must have taken about an hour; I was deliberately taking my time. At one point during the edge permutation, I realized my mental map contained a duplicate piece, so I had to go back to an earlier map and replay the moves I had made to correct things. That took quite a while, but I did manage to correct it.
If you like blindfold cubing, you might also be interested in learning about some other curiosities I enjoy: mathemagics (also called human calculators), memory tricks and card magic.
Many thanks are due to Richard Carr for his excellent description of blindfold cubing. Also to the developer(s) of Cube Explorer which allowed me to practise without a cube.