No. 99: May-Jun 1995
In 1994, J. Wilding and E. Valentine, both at the University of London, provided the British Journal of Psychology with two studies of people claiming to have exceptional memories. In their second paper (Ref. 2), they detailed the mental workings of TM, a 25-year-old male, and an accomplished user of mnemonics. TM astounds audiences with his seemingly impossible memory feats. These feats, however, are no mystery to TM, and he has carefully explained how it is all mnemonics and nothing paranormal. But there remains the clear implication is that the normal human mind is underestimated and underused.
TM's "performances" involve six demonstrations, two of which we now elaborate upon.
Demonstration 2. TM asks audiences for birthdates and very quickly gives the day of birth. He has explained this "gift" thusly:
"The day of birth calculations were originally carried out through use of a system of numerical codes for years and months which were combined and subjected to certain calculations. However, with practice many shortcuts and mnemonics have been developed and now TM often knows instantly that certain dates imply certain days, like learning the multiplication table. Every year and month has a code from 0 to 6 and TM has learned the codes (by the method explained below) for all years from 1900 to 2000. For any given date the method is to add the codes for the month and the year and divide the total by 7; the remainder gives the day of the week. For example, 27 October 1964 gives 27 + 1 (the code for October) + 3 (the code for 1964) = 31. Dividing by 7 gives a remainder of 3 which is the third day of the week, Tuesday." (Ref. 2)
Note the connection between TM's feats and those of those idiot savants adept at calendar-calculating.
Demonstration 3. TM quickly gives the telephone number of any of the 15,000 hotels listed in a large directory.
"The telephone have been learned through a mnemonic system for encoding numbers as a series of two-digit pairs. Each pair has a learned associate (e.g. 00 is a bicycle, 57 is tomato sauce, 39 is Hitler, 41 is mum, his mother's age when he started this system). For larger numbers these associates are combined into wholes which are usually highly imageable (a bottle of tomato sauce riding a bicycle) and attached to some other associate to the hotel name." (Ref. 2)
TM's mnemonics seem weird, but they work; and they probably could work for anyone -- for we barely tax our mental powers in modern life. But would our latent mental capabilities been of use to ancient man, or is this still another case of "evolutionary overshoot", as we harped on so heavily under BIOLOGY in this issue?
1. Wilding, John, and Valentine, Elizabeth; "Memory Champions," British Journal of Psychology, 85:231, 1994.
2. Wilding, John, and Valentine, Elizabeth; "Mnemonic Wizardry with the Telephone Directory -- But Stories Are Another Story," British Journal of Psychology, 85:501, 1994.