I find it unbelievable that Arthur Jensen now regards the data of Sir Cyril Burt on identical twins reared apart as in any way genuine and of serious scientific value (Books, THES , August 8).
All Burt bequeathed us was a single typewritten sheet giving the twins' final "assessments" of intelligence and ratings for the environments into which they were allegedly placed. We have no reliable details concerning the age of twin, when, where and by whom, and with which test the twin was investigated. His ethereal co-workers, without whose assistance he could not have compiled his large sample of twins, have simply failed to materialise.
On a positive note, it is a good thing that Jensen's book has appeared and not suffered the same fate as Chris Brand's The g Factor , which was "de-published". An open discussion of controversial issues such as intelligence, race and genetics is surely preferable to their suppression by the forces of political correctness.
Richard E. Rawles
Senior lecturer in psychology
University College London