Unlike in physics, the category of thought experiment is not very common in biology. At least there are no classic examples that are as important and as well-known as the most famous thought experiments in physics, such as Galileo’s, Maxwell’s or Einstein’s. The reasons for this are far from obvious; maybe it has to do with the fact that modern biology for the most part sees itself as a thoroughly empirical discipline that engages either in real natural history or in (...) experimenting on real organisms rather than fictive ones. While theoretical biology does exist and is recognized as part of biology, its role within biology appears to be more marginal than the role of theoretical physics within physics. It could be that this marginality of theory also affects thought experiments as sources of theoretical knowledge. Of course, none of this provides a sufficient reason for thinking that thought experiments are really unimportant in biology. It is quite possible that the common perception of this matter is wrong and that there are important theoretical considerations in biology, past or present, that deserve the title of thought experiment just as much as the standard examples from physics. Some such considerations may even be widely known and considered to be important, but were not recognized as thought experiments. In fact, as we shall see, there are reasons for thinking that what is arguably the single most important biological work ever, Charles Darwin’s On the Origin of Species, contains a number of thought experiments. There are also more recent examples both in evolutionary and non-evolutionary biology, as we will show. Part of the problem in identifying positive examples in the history of biology is the lack of agreement as to what exactly a thought experiment is. Even worse, there may not be more than a family resemblance that unifies this epistemic category. We take it that classical thought experiments show the following characteristics: They serve directly or indirectly in the non-empirical epistemic evaluation of theoretical propositions, explanations or hypotheses. Thought experiments somehow appeal to the imagination. They involve hypothetical scenarios, which may or may not be fictive. In other words, thought experiments suppose that certain states of affairs hold and then try to intuit what would happen in a world where these suppositions are true. We want to examine in the following sections if there are episodes in the history of biology that satisfy these criteria. As we will show, there are a few episodes that might satisfy all three of these criteria, and many more if the imagination criterion is dropped or understood in a lose sense. In any case, this criterion is somewhat vague in the first place, unless a specific account of the imagination is presupposed. There will also be issues as to what exactly “non-empirical” means. In general, for the sake of discussion we propose to understand the term “thought experiment” here in a broad rather than a narrow sense here. We would rather be guilty of having too wide a conception of thought experiment than of missing a whole range of really interesting examples. (shrink)

In the first edition of the Origin of Species, Charles Darwin apologized for not correctly referencing all the works cited in his magnum opus. More than 150 years later we have catalogued these citations and analyzed the resultant data. Looking for a complete selection of collaborators, a flexible interpretation of the term citation was necessary; we define it as any reference made to a third party, independently of its form or function. Following the same idea, the sixth edition of the (...) Origin, originally published in 1872 and reprinted with minor additions and corrections in 1876, was chosen for the research because it represents the end of a long debate between Darwin and his peers. It naturally is the edition with the greatest number of citations and collaborators. Through a diverse theoretical analysis, we aim to present a new perspective for the study of the Origin of Species: a bibliographic approach that provides the tools needed to understand the history of the book as a physical and cultural object. Bibliometrics provides a theory of citations as well as a quantitative analysis; science studies highlights the profound social aspects of science in the making. The analysis resulted in 639 citations to 298 collaborators and provided a new perspective of the rhetorical structure of the Origin, even though these results are only the tip of the iceberg of the potential of all the data gathered in this study. (shrink)

Structurally, cognitive and biological evolution are highly similar. Random variation and constant but blind selection drive evolution within biology as well as within cognition. However, evolution of cognitive programs, and in particular of grammar systems, is not a subclass of biological evolution but a domain of its own. The abstract evolutionary principles, however, are akin in cognitive and biological evolution. In other words, insights gained in the biological domain can be cautiously applied to the cognitive domain. This paper claims that (...) the cognitively encapsulated, i.e. consciously inaccessible, aspects of grammars as cognitively represented systems, that is, the procedural and structural parts of grammars, are subject to, and results of, Darwinian evolution, applying to a domain-specific cognitive program. Other, consciously accessible aspects of language do not fall under Darwinian evolutionary principles, but are mostly instances of social changes. (shrink)