Time to get knotted

It is unfortunate that Leonard Susskind's vitriolic and intemperate attack on two critics of string theory ("Hold fire! This epic vessel has only just set sail...", August 25) should have appeared in the same issue as - and not after - P. W. Anderson's book review titled "Loose ends and Gordian knots of the string cult".

For Anderson, a distinguished theoretical physicist and Nobel laureate who has made seminal contributions in many branches of physics, can hardly be accused of being a "mid-level theoretical physicist" or a member of the "Chicken Little Society".

Moreover, Susskind's defence of string theory not only failed to address Anderson's key criticism of string theorists - namely that their theorising is not grounded "on the acute observation of nature" - but rather reinforced this impression.

The criticism of string theorists, then, is not just that they fail to make predictions that are in principle falsifiable by experimental observation, but that they have abandoned the Bacononian philosophy of science.

Anderson's warning shot across the bow of the Good Ship String Theory is very reminiscent of Paul Dirac's complaint of Albert Einstein's unsuccessful post-1924 activity when he opined that Einstein should stop telling the good Lord what to think.

William Barford
Oxford