Sir — Can we comprehend the ideas andthoughts of other beings? The scientificliterature from a variety of fields, includingpsychology, sociology and ethics, suggeststhat we can. The methodology used in thedisciplines of genetics, psychology, animalbehaviour, sociology, history, publicunderstanding of science, and religiousstudies — to mention only a few — canand should be collected to design anintegrative approach to understand theextent of human ideas. Readers are invitedto a meeting in Japan on 15 February 2003to start such a project (see www.biol.tsukuba.ac.jp/~macer/index.html).

If we define an ‘idea’ as the mentalconceptualization of something —including physical objects, an action orsensory experience — then the number of objects in the universe of a living beingis finite. Both the number of possiblechoices for action and the sensory states of animals are finite. In that sense we canexpect to be able to count ideas. The initialmethodology could separate classes of

ideas, as follows: (1) conceptualization ofphysical objects; (2) psychological meaningsof images associated with objects (such as colours); (3) memories; (4) plans forshort- and long-term future; (5) intentionto modify one’s behaviour; (6) intention tomodify behaviour of surrounding beingsand the environment; (7) sensory statessuch as pain, pleasure, libido; (8) inhibitionof a response based on immediateevolutionary benefit, for example, memes;and (9) interactive conceptualization ofideas in a community-based response.

I propose a ‘mental mapping project’ to explore similarities between cultures and communities, both at the individualhuman level and as members respondinginside biological communities. There areimplications for cultural identity. Howshould the culture that tries to maintain itsuniqueness face up to the reality that thefull range of idea diversity is found in everyculture? Idea diversity is found in almost allcultural groups, excluding those formed topromote particular political aims, such as

those who fight for or against the right tochoose abortion or euthanasia.

The universality of ideas is importantfor the development of global society,when we’re faced with dilemmas such aswhether to have common internationalguidelines to regulate the use of newbiotechnology, for example, or of assistedreproductive technology using cloning. Itis time to start thinking scientifically aboutthis in a coordinated way.

Although the human mind appears to be infinitely complex, and the diversityof humankind and culture has beenconsidered vast, I would suggest that thenumber of ideas that human beings have isfinite. Hence my call for a project to mapthe ideas of the human mind. We alreadyhave the means to embark upon a humanmental map with the goal of describing thediversity of ideas a human being makes inany given situation or dilemma.Darryl R. J. MacerInstitute of Biological Sciences, University ofTsukuba, Tsukuba Science City 305-8572, Japan

correspondence

NATURE | VOL 420 | 14 NOVEMBER 2002 | www.nature.com/nature 121

The next challenge is to map the human mindAn ambitious project aims to chart the territory of ideas: vast but, conceivably, not infinite.

Moving beyond ‘industryvs ecologists’ stereotypeSir — I agree with your statement in yourNews story about my ‘superweed’ research(Nature 419, 655; 2002) that academicresearchers need better access to pre-commercial transgenes to be able to carryout independent, empirical research onenvironmental risks of geneticallymodified organisms (GMOs). Yet thefragile relationship between seedcompanies and university researchers isimproving, and readers may not get thisimpression from your story.

A small community of ecologists andpopulation geneticists is working withagricultural biotechnology companies andregulatory agencies to assess the environ-mental effects of transgenic crops. In mycase, two multinational companies invitedmy colleagues and me to evaluate theeffects of pre-commercial Bt sunflowers on wild sunflowers, which are a commonweed in the midwestern United States. The companies agreed to fund a researchproject that would be published independently in peer-reviewed journals(A. A. Snow et al. Ecological Applications; in the press). They provided us with a Bttransgene in a cultivated sunflower, as wellas valuable technical assistance.

This liaison was not always easy, ascompanies are bound by confidentialbusiness plans whereas academic

ecologists are eager to talk about work in progress. I’m glad we carried out thisresearch, even though it was frustratingwhen we were not allowed to continueusing university funds. The companies had decided not to commercialize thisvariety of Bt sunflower, but we wanted to carry out a larger-scale project becauseso little is known about the ecological and evolutionary effects of transgenes that could spread throughout naturalpopulations.

Unfortunately, polarization of views onGMOs often hinders the use of ecologicalresearch in risk assessments. Seed companieshave been slow to acknowledge thatecological studies are needed to evaluatesome of their products. They also fear themedia’s tendency to emphasize unwelcomefindings and ignore results showingenvironmental benefits or ‘no impact’. Atthe other end of the spectrum, objectionsfrom advocacy groups have reached thepoint where risk assessment research isoften blocked by regulatory delays or eco-terrorism, especially in Europe.

Much of this debate hinges on ethicaland political concerns, which are outsidethe realm of ecological science.Nonetheless, academic ecologists can helpto answer questions that arise about theenvironmental effects of GMOs. I urge thatwe progress beyond the standard stereo-typing of ‘industry versus ecologists’ tofacilitate more effective dialogue and to

introduce sounder science to the debate.Allison A. Snow Department of Evolution, Ecology and Organismal Biology, Ohio State University,Columbus, Ohio 43210, USA

Liberal world of scienceSir — Raymond Pierotti’s Correspondenceexpressing his opinion (Nature 419, 667;2002) that academic scandals are less wellknown than business ones reminded me of Michael Faraday’s description of his“desire to escape from trade, which Ithought vicious and selfish, and to enterthe service of Science, which I imaginedmade its pursuers amiable and liberal”.

Faraday, a bookseller’s apprentice, hadwritten to Sir Humphry Davy at the RoyalInstitution of Great Britain in pursuit of a career move. Davy advised him thatexperience would correct his opinion ofthe “superior moral feelings of philosophicmen” (see The Philosopher’s Tree, ed. P. Day, 2–3; IoP, Bristol, 1999).

Business and science have long beeninterdependent. Faraday’s “philosophic”researches, for example, paved the way forvast technologically based industries andmany other scientific, technological andbusiness developments. Geraint Day Policy Unit, Institute of Directors, 116 Pall Mall,London SW1Y 5ED, UK

© 2002 Nature Publishing Group