Alberto Vanzo writes…
[E] To endorse the method of (early modern) experimental philosophy is to believe that one should only firmly commit to those substantive claims and theories that are warranted by experiments and observations.
In this post, I will clarify three related points in order to address some misunderstandings concerning the nature and the usefulness of the notion of experimental philosophy. I will make three claims. First, experimental philosophers did not need to eschew any theories altogether. Second, this does not entail that even Descartes, Leibniz, or some Scholastics were experimental philosophers. Third, the difficulty in classifying certain authors as experimental philosophers is not as worrying as it is sometimes portrayed.
Experiments and theories
As it should be clear from [E], one need not take on a fully a-theoretical attitude in order to endorse the method of experimental philosophy. The Proem of the Saggi di naturali esperienze, alongside other texts by experimental philosophers, states that the sole purpose of the Accademia del Cimento is “experimenting and narrating”, while eschewing any “hint of anything speculative”. Nevertheless, experimental philosophers were not required to completely avoid any theories. Those who endorse the method of experimental philosophy can consistently entertain theories, put them forward as hypotheses to be tested experimentally, reject theories that are incompatible with experimental evidence, tentatively or provisionally endorse the theories that they take to be more probable than their competitors, and even firmly endorse certain theories (such as corpuscularism), insofar they are warranted by experience. In the light of this, Boyle, Hooke, Locke and Newton can be said to have endorsed the method of experimental philosophy, even though they did not endorse the fully a-theoretical stance that is often associated with the movement.
Who wasn’t an experimental philosopher?
One may fear that, once we grant that experimental philosophers could be engaged in some forms of theorizing, the notion of experimental philosophy becomes too inclusive, so that Descartes, Leibniz, and even certain Aristotelians can be classed as experimental philosophers. This is not the case. The fact that an experimental philosopher can endorse theories and substantive natural-philosophical claims does not entail that there is no real distinction between those who endorsed and those who did not endorse the method of experimental philosophy.
Descartes and Leibniz too engaged in experiments. Leibniz even claimed to be “strongly in favour of the experimental philosophy”. However, insofar as Descartes thought that he had firmly established the highly speculative cosmogonical theories of the Principles of Philosophy, in spite of the scant empirical evidence with which he backed them up, he was hardly following the methodological prescription spelt out in [E]. As for Leibniz, although he stressed the importance of experience for natural philosophy, he also held that some basic propositions of natural philosophy (like the principle of uniformity of nature) could be established only a priori. This view is incompatible with [E], we should not take Leibniz to be an experimental philosopher even though he stressed the importance of experience.
Problems of classification
Although there is a real distinction between those who endorsed the method of experimental philosophy and those who did not, establishing whether an early modern author really was an experimental philosopher is sometimes difficult. There can be a disconnect between rhetoric and methodology, or methodology (understood in the etymological sense of method-talk) and actual, practised method.
Some philosophers called themselves experimental philosophers, or endorsed the rhetoric of the movement (e.g. using “hypothesis” and “speculation” as a term of abuse), but they thought they were entitled to endorse certain natural-philosophical claims a priori. Others claimed that they were following the method of experimental philosophy, but they endorsed theories that outstripped the empirical evidence. Leibniz, as we have seen, is an example of the disconnect between rhetoric and methodology. Another example is provided by those Jesuits, like Daniello Bartoli, who rehearsed the experimentalist rhetoric, but attempted to take the sting out of experimentalism and to combine it with some Aristotelian doctrines that were hardly warranted by experience. In other cases, there was a disconnect between methodology and actual method. An example is provided by the account of vision of the late seventeenth-century Italian natural philosopher Francesco Bianchini. Not only his rhetoric, but also his methodological pronouncements were in line with [E]. However, his account of vision was far more speculative than those pronouncements allowed.
The disconnect between rhetoric, methodology, and practised method determines a difficulty in establishing whether certain authors were experimental philosophers. This would be worrying if a primary aim of the study of early modern experimental philosophy were providing a handy classification of early modern authors. However, the point of studying early modern experimental philosophy is not pigeonholing early modern authors, but understanding their philosophical views and practices, even when the former were not in line with the latter. Finding these discrepancies should not be surprising. People sometimes fail to practice what they preach. Other times, they use a rhetoric that is at least partly out of step with their actual views. Early modern philosophers were no exception.