Sir

The International Council for Science (ICSU) welcomes your timely publication of the Commentary by Blakemore et al., “Is a scientific boycott ever justified?” (Nature 421, 314; 2003). We are pleased that the authors draw a conclusion directly aligned with ICSU's 'universality of science' principle (see http://www.icsu.org/Library/Central/Statem/freecondsc.html) — that the unrestricted flow of scientific ideas and information is critical to the advancement of science — in stating that there would be few, if any, circumstances in which the principle should be overridden.

Since its inception in 1931, ICSU has affirmed the fundamental rights of scientists to pursue research and publish results, to associate freely, and to share materials. We have publicly upheld this principle through the political and social turmoil of the Second World War, the Cold War and apartheid. Our work to protect the rights of individual scientists — often undertaken out of the limelight — has been steady and successful.

As Blakemore et al. suggest, each situation is unique and calls for a considered response, not just from ICSU, but also from its members (the 101 national members and 27 scientific unions for which adherence to the principle is a condition of membership) and from the entire scientific community.

The Commentary was prompted by a call — made by Blakemore, his co-author Richard Dawkins and 123 other academics, in a letter to Britain's Guardian newspaper on 6 April 2002 — for national and European agencies to suspend Israel's eligibility for academic funding until Israel agreed to abide by UN resolutions and open serious peace negotiations with the Palestinians. Others subsequently called for boycotts of Israeli scientists, and two journals decided to exclude Israeli scholars from their editorial boards. (See also Correspondence by M. Fainzilber, Nature 417, 15; 2002; and by S. Rose & H. Rose, A. Abbes et al., and M. Mangel, Nature 417, 221; 2002 and Nature 417, 222; 2002.)

These events prompted ICSU to issue a public statement denouncing the proposed boycotts to our membership and the media in September 2002 (see http://www.icsu.org/Media/press/pdf_releases/release1.htm).

Recognizing that the Israeli boycott issue is only one example of the current threats to the universality principle, ICSU is reviewing the principle in the context of the twenty-first century. We are closely monitoring additional calls for boycotts of Israeli scholars in the French scientific community, as well as security measures that effectively limit the publication of scientific data. We have actively voiced our concern regarding visa regulations that restrict the travel of scientists from specific countries and/or disciplines.

Blakemore et al. have highlighted apparent definitional ambiguities in the principle as currently worded, identifying ethical dilemmas (individual and institutional) that warrant consideration. In today's environment, threats to the principle are as likely to arise from the activities of individuals or small groups as from the policies of a particular government. Clearly, ICSU needs to develop strategies to address these new circumstances. As we undertake this important task, we welcome input from the broad scientific community. In advance of its meeting, scheduled for March, ICSU's Standing Committee on Freedom in the Conduct of Science (SCFCS) invites readers to forward additional questions and comments to its chair, Peter Warren, at peter.warren@beech5.demon.co.uk.