a field that merged the two disciplines. Further from chemistry, in hydrology and geography, Gilbert White was paying no attention to the traditional bounds of any academic subject as he studied how we use and might use water. In other words, I would like to challenge the dogma that science has increasingly become more interdisciplinary. What I propose is that we have merely found it fashionable to institutionalize cross-disciplinary activity that was already happening and evolving in a healthy manner.
Suppose we grant that my challenge contains at least a little truth. What do we accomplish by institutionalizing interdisciplinary research? One change I suspect has happened, but would find it very difficult to support with hard evidence, has to do with another kind of change closely related to this interdisciplinary issue. While people were working across borderlines 40 years ago and more, other people were working in some subfields of chemistry that had become “mature” in the most pejorative sense of that word. In that period, many of my contemporaries and I looked on classical analytical chemistry and electrochemistry as fields supported by an ingrown, myopic community that had lost a larger vision. Analytical chemistry evolved out of that slough and became a much livelier subject when it looked beyond its traditional boundaries and decided that those boundaries had become irrelevant. Rather, the fundamental questions of how to make reliable determinations of what was present and how it behaved became again the focus of the subject.
Another subject that collected specialists who turned from fundamental scientific problems to solving challenging puzzles was, for some years, the synthesis of natural products. It, too, became a “mature” subject with its own rules. When Gobind Khorana used bugs to synthesize intermediates for his eventual synthesis of Coenzyme A, he violated the rules of the game and was considered déclassé for doing so. Again, synthetic organic chemistry has outgrown that stage and is again a healthy science, in part because its practitioners have looked outside traditional disciplinary bounds and flirt regularly with materials scientists. In what field do they work? I consider that an irrelevant question. It is more important to ask, What interesting and important problems are they addressing, and have they the skills (or access to the skills) appropriate to those problems?
One other “mature” area comes to mind that, according to my prejudices, has not yet emerged from its slough. This opinion will raise hackles, notably among its practitioners, who have been slow to recognize the maturation. This is the area of quantum chemistry, the application of computational methods to determine the properties of atoms and molecules (and sometimes, for the more interdisciplinary sorts, of solids and even liquids and polymers) by solving quantum mechanical equations. I would certainly not deny that people in this field have been making progress with the methods for doing such calculations. What I would raise is the question of whether the problems being addressed by that rather closed community have evolved into problems “within the club” and have become problems whose answers are of little interest to the rest of the scientific world. Can that community explain persuasively why their achievements are interesting to people working in materials science, or molecular biology, or atmospheric chemistry, or fundamental quantum mechanics? But there are fundamental, important, and potentially productive questions standing open in this field. Can anyone recast the formally exact density functional theory developed by Pierre Hohenberg and Walter Kohn, starting with first principles, in a form whose lowest approximation is the ubiquitous (but still only ad hoc) local-density approximation, that would also reveal how to make further refinements of this powerful approach?
Thus, I infer that interdisciplinarity has had a healthy effect in pulling “mature” disciplines back into true scientific import. Institutionalizing the interdisciplinarity is a way of making it financially attractive to look beyond traditional bounds. Whether such institutionalizing has also increased true intellectual interactions is a question I cannot answer, but as I indicated, I am somewhat skeptical that it has. To establish whether it has would require a serious survey, and even if conducted the survey would be