Of Minds and Molecules: New Philosophical Perspectives on Chemistry. Nalini Bhushan and Stuart Rosenfeld, eds. xvi + 299 pp. Oxford University Press, 2000. $55.
Philosophy of physics and philosophy of biology are well-established subdisciplines of the philosophy of science, so why not philosophy of chemistry? I remember posing this question as an undergraduate chemistry major to my first philosophy instructor, a well-known philosopher of science. He pondered the question awhile and answered that he didn't really know, that perhaps there are no interesting philosophical questions in chemistry. This is a view challenged by Nalini Bhushan and Stuart Rosenfeld in Of Minds and Molecules, a new collection of 15 essays about philosophy of chemistry.
The unwarranted neglect of chemistry by philosophers of science came about mostly by historical accident. Early 20th-century philosophy of science was dominated by individuals trained in mathematical logic or physics. In addition, Einstein's work challenged long-standing ideas about the nature of time and space, directing much philosophical attention toward physics. Since then, philosophers of science have often been drawn to areas characterized by significant foundational disputes or unclear or ambiguous basic concepts—properties generally not attributed to chemistry.
The contributors to this book are philosophers, chemists and philosopher-chemist teams (including the editors). Collaboration between philosophers and chemists is one of its most exciting features; it focuses the discussion on the application of traditional topics in philosophy of science to chemistry and on previously unexplored topics native to chemistry.
The editors claim in their introduction that the unifying theme of the essays is a challenge to reductionism—the thesis that the theories and explanations of chemistry can be derived from fundamental physics. But in my view the book's most important message is that chemistry has philosophically interesting features not shared with other sciences and therefore deserves attention in philosophical discussions of science. These unique features need to be understood before we can have anything like a complete philosophical picture of science.
Although not all of these essays have an antireductionist theme, the topic is covered quite thoroughly. Reductionism has dominated the literature on philosophy of chemistry, and discussions of reduction are among the most theoretically mature in the book. The contributors do not hold a unified view, but they all conclude that simple claims about chemical theories being reducible to physics are dubious and misleading.
Another traditional topic covered, with a chemical twist, is the role of models in scientific theories. Some accounts of scientific explanation claim that to explain a phenomenon is to derive its occurrence from a law of nature; however, some of the contributors argue that highly idealized models, not laws of nature, play the explanatory role in chemistry. Another theme explored is the importance of iconic or pictorial models in chemical discourse. Logical Empiricist philosophy of science took it as a given that scientific theories and explanations could be represented symbolically—specifically, using first-order logic. This, one of the essays argues, is impossible in chemistry.
Several essays focus on traditional philosophical themes related to structure and identity. One essay argues that macroscopic substances, not molecules, are the basic units of chemistry. Another deals with the status of molecular shape. Consider the straightforward claim that molecular properties, including molecular shape, explain the behavior of substances. Quantum mechanics tells us that molecular shape cannot be an intrinsic property of a molecule. Why, then, is it acceptable to invoke molecular shape in explanations of the behavior of molecules? The answer, this essay argues, lies in recognizing that molecular shape is a property partially constituted by the means of its detection.
Synthesis, instrumentation and the chemical senses—important but often overlooked topics—are also discussed. Synthesis has been neglected entirely in philosophy of science even though it is a central activity of chemistry and poses interesting questions about natural kindhood. Are synthetic molecules natural kinds like water, or artifacts like tables and chairs? The essays on instrumentation and the chemical senses invite us to reconsider traditional philosophical ideas such as the distinction between observation and theory. Should we, for example, treat spectroscopy as an extension of our perceptual abilities? If we do, how might this change our accounts of how theories are supported by perceptual evidence? Given the neglect of these topics, how would classical discussions about the nature of science have been different had chemistry been the paradigm instead of physics?
Although the ideas in this book are genuinely interesting and philosophically important, the arguments in some of the essays lack rigor and depth. Several authors either ignored or misunderstood the relevant philosophical literature. Many complicated ideas or claims are only explained in a paragraph or two, and many of these paragraphs do not contain convincing arguments. Some of the essays also fail to consider obvious objections and respond to them. In many cases, a significant amount of argumentation and conceptual clarification would be necessary to turn the ideas into fully argued philosophical positions.
But these criticisms shouldn't overshadow the book's importance. Of Minds and Molecules is the beginning of a new literature for a relatively new subdiscipline. Creative philosophers could easily use any one of these essays as the starting point for a very interesting exploration of chemistry. Issues in philosophy of chemistry may not raise the kind of deep conceptual perplexity that the quantum mechanical measurement problem raises, and they may not be as conceptually complex as debates about optimality arguments in evolutionary biology. They are, however, essential to understanding what makes science work and progress.
Of Minds and Molecules is reasonably accessible. Very little philosophical knowledge is presupposed by most of the essays; however, a few are fairly technical. Knowing a little chemistry would help the reader be more critical of some of the claims advanced. Overall, I recommended the book to anyone with a serious interest in the philosophy of chemistry or philosophy of science more generally.—Michael Weisberg, Philosophy, Stanford University