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Monthly Archives: October 2012

Feijoo and his ‘Magisterio de la experiencia’ (lessons of experience)

Juan Gomez writes…

I have posted on this blog regarding early modern experimental philosophy in Spain (here and here). Contrary to the common opinion that Spain in the seventeenth and eighteenth centuries was a ‘backwards’ nation when compared to France and England, I have pointed out how many Spanish thinkers were aware of and advocated for the application of the ‘new’ science. In today’s post I want to focus on a text by the thinker who is arguably one of the most influential figures in Spanish thought, Benito Jerónimo Feijoo.

Feijoo was born in 1676 and ordained under the order of Saint Benedict in 1690 after studying in the monastery of San Vicente de Salamanca. He moved to Oviedo in 1709 where he taught and developed his philosophical work. The most influential of his texts was the Teatro Crítico Universal, a nine volume work published between 1726 and 1740. Each of the volumes contains a number of essays on a variety of topics including natural philosophy, history, medicine, women, education, transubstantiation, and religion. I want to focus on a discourse from the fifth volume (1733) titled ‘El gran magisterio de la experiencia’ (The great lessons of experience).

The piece is an essay on the danger of pure speculation (‘reason unaided by experience’) and calls for the emphasis on experience and observation in all our inquiries. Feijoo begins by recounting a fable that was read to him from a French book by a foreign traveller. The story begins with the arrival of two ladies, Solidína and Ideária, in the Kingdom of Cosmósia with the intention of taking dominion over the Kingdom. Solidína was ´wise but simple,’ and her strategy for conquering the empire was the following:

    She went from house to house, making herself acquainted with everyone, teaching with clear and common voices true and useful doctrines… since everywhere she found sensible objects that examined through the ministry of the sense became the books for her lessons. Far from inspiring an indiscreet presumption among her disciples, she told them with humbleness that what she could teach was very little compared to the infinite amount there is to learn, and that to achieve even just an average knowledge of things immense work and discipline was necessary.

Ideária on the other hand was ‘ignorant but charlatan’ and had a very different strategy:

    She tried to establish an absolute despotism over her disciples, expediting an edict so that no one would believe what their eyes saw or what their hands felt… their disciples started to believe many maxims that used to be seen as impediments to knowledge: that truth can only be known through fiction; that there is a way of knowing things that a boy can learn in four days; that there is one man, that is all man (the same goes for all species), so that if one is known, all are known; that non-sensitive and inanimate things have their appetites, ears, and loves no less than sensitive and animate things… that all living beings are composed by a considerable degree of fire, not even excluding fishes, even though they are always under water.

Ideária ruled for a long time until there was a schism among her disciples. A subject named Papyráceo separated himself and introduced new dogmas:

    That all living beings (except men) are nothing but corpses; that even in man only a small part of the body entertains the presence of the soul; that the world is infinitely extended; that the movement of sub-lunar and celestial bodies is perennial; that imaginary space is a true and real body… that in all things imagination must be believed, and never the senses; and the latter deceive in all their representations; that the swan is not white, nor the crow black, nor fire hot, nor snow cold &c.

But fortunately the story does not end with Ideária’s rule. People found out that the maxims both her and Papyráceo defended were at most probable, so they remembered Solidína and brought her back to the city:

    They established her as the magnificent of the teaching rooms, where she teaches with more and more credit each day, contributing immensely to the favour of some great heroes, especially the two princes, Galindo and Anglosio, who are very fond of Solidína.

Feijoo goes on to explain the themes and characters the story alludes to, which are not that difficult to discern. Cosmósia is the world, coming from the Greek cosmos. Solidína is experience, since it ‘explains solidly its maxims with sensible demonstrations.’ Ideária is imagination, since it ‘founds its opinions on the vain representation of its ideas.’ The triumph of this kind of philosophy is represented by Pythagoras, Plato and Aristotle, out of whom came an ‘ideal physics instead of a solid and experimental one.’ The character of Papyráceo alludes to Descartes, since the former comes from the Latin word Papyrus, which is equivalent to the French ‘Carte’. Finally,

    experimental observation, which was only used before by the farmers for the cultivation of the crops, the due care of the fields and the propagation of livestock, was recently brought back pompously by some institutions set up to examine nature in this way. Among them, the most famous being the Royal Academy of the Sciences in Paris and the Royal Society of London chartered under the Monarchs of France and England, respectively, which are alluded by the princes Galindo and Anglosio, derived from the Latin terms for those nations, Gallia and Anglia.

It is clear from this introduction to Feijoo’s essay that he is promoting this picture of the history of philosophy as a very long and detrimental period where the way of doing philosophy without consideration for experiment and observation was superseded by the new method in the seventeenth century, as it is exemplified by the Royal institutions of France and England. And this just sets the scene for the rest of what Feijoo wants to say. In my next post I will explore Feijoo’s more detailed objections to the use of pure speculation and his call for experimental observation as the foundation of all knowledge.

Laura Bassi: An Eighteenth-Century Newtonian

Kirsten Walsh writes…

Laura Bassi (1711-1778) had a remarkable career.  In eighteenth-century Italy, it was rare, but not unheard of, for a woman from a wealthy family to receive a higher education, a doctorate, or even a lectureship.  But what made Bassi unique was how she used her positions at the University of Bologna and the Academy of Science (which would ordinarily have been symbolic) to contribute to the scientific community of Europe.

Thony Christie over at The Renaissance Mathematicus recently wrote a very good post about Bassi’s life and career, so I will not go into those details here.  Instead, today I’m interested in Bassi as an eighteenth-century Newtonian and experimental physicist.

Over the course of her career (roughly 1732 to 1778), Bassi presented papers on mathematics, pneumatics, fluid dynamics, mechanics, optics and electricity.  Most of these papers have been lost, but the few surviving papers display Bassi’s talent for mathematics and her commitment to the Newtonian method (as exemplified by Principia).  For example, in her paper on differential calculus (“De problemate quodam mechanico”, 1757), Bassi dealt with the problem of how to determine the motion of the centre of mass of two or more bodies moving along any curved paths in a plane.  In this paper, she followed the Newtonian method of avoiding metaphysical and empirical assumptions about the nature of matter.

From the 1740s onwards, Bassi and her husband  Giuseppe Veratti became very interested in electrical phenomena.  Here, we can identify two different Newtonian themes.  Firstly, their research appears to have been heavily influenced by the later queries of the Opticks, which attempt to link phenomena such as light, heat, electricity and magnetism with biological phenomena such as muscle movement, growth of plants and phosphorescent fish.  Secondly, they supported Franklin’s electrical-fluid theory, which had been systematised in a Newtonian framework by Beccaria.

In the late 1740s, Bassi began teaching privately.  Bassi and Veratti had a well-equipped physics laboratory in their home, including an electricity machine.  This made it possible for Bassi to teach experimental physics in their home.  At the University, the philosophical curriculum was essentially scholastic, and at the Institute of Sciences, the courses on experimental physics had a physiological focus (which reflected the interests of the Bolognese scholars, most of whom had medical degrees).  Bassi’s knowledge-base, which by then included advanced mathematics, mechanics, optics, and electricity, made her uniquely qualified to teach a course on Newtonian philosophy and Franklinian electricity.  In a letter to Scarselli in 1755 she mentioned the popularity of her classes: “The classes have gathered such momentum that they are now attended by people of considerable education, including foreigners, rather than by youths”.

From this brief survey of Bassi’s work, she appears to have adopted many facets of Newtonianism: she accepted and built on Newton’s rational mechanics, but also followed the leads left by Newton in his optical queries.  Indeed, in her own time, Bassi was a well-known Newtonian.  Algarotti mentioned her several times (although not by name) in his Sir Isaac Newton’s Philosophy explain’d for the use of the Ladies and explicitly presented her as a Newtonian in ‘Non la lesboa’ – his contribution to the book of poems published in honour of Bassi’s graduation.  Also, in 1744 Voltaire implicitly compared Bassi with Newton when he wrote:

    Most Honoured Lady: I would like to visit Bologna so that I might say to my fellow citizens that I have seen Signora Bassi, but, deprived of this honour, I trust that I may with justice cast at your feet this philosophical homage in reverence to the glory of her century and sex.  As there is no Bassi in London I should more happily enter your Academy of Bologna than the English one, even though it may have produced a Newton.

But what can we say about Bassi’s ‘experimental physics’?  The subject-matter was certainly Newtonian, but what about the methodology?  On this blog, we have argued that, from the 1690s onwards, the experimental philosophy was approached in a way that emulated Newton’s mathematical-experimental method.  Bassi certainly had the expertise to follow the Newtonian method, which raises the question: Should Bassi’s experimental physics be seen as another facet of her Newtonianism, or should we regard it as a more general interest in the experimental method?

Unfortunately, I haven’t been able to find the evidence to answer this question.  I’m not even sure if Bassi engaged in any kind of methodological reflection.  Does anyone know how I might find out?

Cartesian Empiricisms – a Reply

Peter Anstey writes …

The forthcoming book Cartesian Empiricisms edited by Mihnea Dobre and Tammy Nyden promises to extend our knowledge of the experimental practices and philosophy of experiment amongst many of Descartes’ followers.

Dobre, however, claims that the book will offer more than a study of these writers. He says in his recent post that what we find in these neo-Cartesians ‘seems to escape the ESD’ (experimental–speculative distinction, my italics). In what sense might it be true that Cartesians doing experiments might escape the ESD? Is it that the ESD cannot explain them? Or, more strongly, is it that their experimental practices contradict the central tenets of the actors’ categories of experimental philosophy and speculative philosophy? And what is the value of persisting with the term ‘empiricism’ to describe the neo-Cartesians’ engagement with experiment?

In my view, the fact that some Cartesians performed experiments is of great interest, but it is also grist for our mill: it actually enriches the evidential base for the claims that we have made on this blog and in recent publications. For it shows that, like all other speculative systems, Cartesian natural philosophy was also subject to the court of experiment.

We have never claimed that proponents of speculative systems like Cartesianism were necessarily opposed to experimental verification of their theories. Nor have we ever claimed that all experimental philosophers were adamantly opposed to speculation: some were, but others, like Robert Boyle and Robert Hooke, were not.

We have claimed that the Cartesian vortex theory came to be regarded by many as the archetypal speculative theory in natural philosophy. Indeed, this was the virtually the standard view in England from the late 1690s when the term ‘our vortex’ starts to disappear and Newton’s arguments against the Cartesian system began to be widely appreciated. But none of this implies that our claims about the ESD need somehow to be modified. In fact, there is evidence that distaste for speculative system building and a belief in the need for the construction of Baconian natural histories were constituents of the general methodological background to mid-seventeenth-century Parisian natural philosophy. The first article of the constitution of the Montmor academy, which met in Paris from the mid-1650s to around the time of the formation of the Académie des Sciences, says:

The purpose of the company shall not be the vain exercise of the mind on useless subtleties (subtiltés inutiles), but the company shall set before itself always the clearer knowledge of the works of God, and the improvement of the conveniences of life, in the Arts and Sciences which seek to establish them.

The anti-speculative element here is hard to miss. (Interestingly, none of the articles mention experiment.) Furthermore, it is well known that Christiaan Huygens recommended to Colbert that the newly formed Adadémie construct natural histories after the manner of Verulam.

Henry Testelin: Etablissement de l'Academie des sciences et fondation de l'observatoire (1666)

What I am hoping to glean from Cartesian Empiricisms is an answer to the following question:

Did the Cartesians practise a form of experimental philosophy analogous to that of the Fellows of the early Royal Society?

This question is important for a number of reasons. The work of Trevor McClaughlin on Rohault, for example, has shown that early Cartesians carried out experiments. Yet we still lack a detailed assessment of the nature, theory and practice of experiments amongst the neo-Cartesians in the three decades after Descartes’ death. There is no doubt that they performed experiments for illustrative purposes and repeated many classic experiments for pedagogical purposes. But did they engage in experimental programs with a view to acquiring new knowledge of nature and to modifying and developing natural philosophical knowledge?

What makes this issue particularly pressing is that there is evidence from the late 1650s and early 1660s that the natural philosophers who met in the Parisian academies, such as the Montmor academy which included several prominent Cartesians, performed experiments, but were not really practising experimental natural philosophy. Henry Oldenburg reported to Michaelis in April 1659 that the philosophical academies in Paris: ‘are rich in promises, few in performance’ (Corresp. of Oldenburg, 1: 241). Three months later Oldenburg wrote to Boyle from Paris saying:

we have severall meetings here of philosophers and statists which I carry your nevew to, for to study men as well as books; though the French naturalists are more discursive, than active or experimentall. (Corresp. of Oldenburg, 1: 287)

My hope, therefore, is that Cartesian Empiricisms will answer this very pressing question.

Cartesian empiricisms

Mihnea Dobre from the universities of Bucharest and Nijmegen writes…

As readers of this blog know, the classic division between continental Rationalists and British Empiricists fails to provide an accurate picture of the early modern period. The Otago team has already offered extensive evidence of the complexity of seventeenth-century natural philosophy. Replacing the traditional-historiographical distinction between Rationalism and Empiricism (RED) with actor-category division of experimental versus speculative philosophy (ESD) is one step ahead in getting a more meaningful image of the philosophical debates that marked the formation of modern philosophy and science.

However, in this post, I would like to focus on a different aspect, which seems to escape the ESD distinction and further complicates our image of the late-seventeenth century. At the same time, I take this opportunity to announce a forthcoming volume, Cartesian Empiricisms, which Tammy Nyden and I are co-editing in the Springer series on the Studies in History and Philosophy of Science.

While this juxtaposition between “Cartesianism” (which for a long time has been associated with rationalism, armchair philosophizing, speculative thinking, or a purely theoretically driven philosophical approach) and “Empiricism” (which besides its traditional opposition to “Rationalism” is still preferred by many to describe an approach based on experiment and experimentation) might look odd at first, it sheds, in fact, a completely new light upon the development of natural philosophy in the second half of the seventeenth century.

Descartes’s philosophy has been discussed, interpreted and revaluated constantly in our histories of both philosophy and science. Yet, a more in-depth study of what happens after Descartes’s death is missing. We hope Cartesian Empiricisms will fill this gap, contributing to the exploration of some now-forgotten philosophical figures, which were not only prime representatives of the philosophical debates of their time but were opening the possibility of a more experimentally oriented natural philosophy.

After Descartes’s death in 1650, his philosophy was challenged in various ways and one of the most common forms of attack was to disprove it with empirical evidence.  Take, for example, this curious case from the Philosophical Transactions, one of the first scientific journals. On June 3, 1667, an observational report described the puzzling case of a turtle that was still able to move even with her head missing:

there came a Letter from Florence, Written by M. Steno, which has also somewhat perplext the followers of Des Cartes. A Tortoise had its head cut off, and yet was found to move its foot three days after. Here was no Communication with the Conarium [i.e. the pineal gland]. As this seems to have given a sore blow to the Cartesian Doctrine, so the Disciples thereof are here endeavouring to heal the Wound (p. 480).

Such instances that do not cohere with Descartes’s natural philosophy can be found in various places in the new scientific journals, as well as in public debates and philosophical treatises. A well-known case is that of the collision rules that went through a number of critical evaluations during the 1660s. Physics, anatomy, and psychology are among the most heated areas of contestation for Descartes’s natural philosophy. Cartesians reacted to the new challenges by both trying to complement or correct Descartes’s philosophical corpus with needed additions, but also by incorporating into their practices new methods. Cartesian Empiricisms will highlight such attempts:


Ch. 1. Introduction

Section I: Cartesian Philosophy: Receptions and Context

Ch. 2. “Censorship, Condemnations, and the Spread of Cartesianism” by Roger Ariew

Ch. 3. “Was there a Cartesian Experimentalism in the 1660’s France?” by Sophie Roux

Ch. 4. “Dutch Cartesian Empiricism and the Advent of Newtonianism” by Wiep van Bunge

Ch. 5. “Heat, Action, Perception: Models of Living Beings in German Medical Cartesianism” by Justin Smith


Section II: Cartesian Disciplines

Ch. 6. “The Cartesian Psychology of Antoine Le Grand” by Gary Hatfield

Ch. 7. “Experimental Cartesianism and the Occult (1675-1720)” by Koen Vermeir

Ch. 8. “Rohault’s Cartesian Physics” by Mihnea Dobre

Ch. 9. “De Volder’s Cartesian Physics and Experimental Pedagogy” by Tammy Nyden

Ch. 10. “Empiricism without Metaphysics: Regius’ Cartesian Natural Philosophy” by Delphine Bellis

Ch. 11. “Robert Desgabets on the Physics and Metaphysics of Blood Transfusion” by Patricia Easton

Ch. 12. “Rohault, Regis and Cartesian Medicine” by Dennis Des Chene

Ch. 13. “Could a Practicing Chemical Philosopher be a Cartesian?” by Bernard Joly


It is particularly interesting how many of the individual Cartesians discussed in this volume blend theoretical and experimental elements. Experience and experimentation become – for some of them – constitutive parts of their Cartesian natural philosophies, thus making it harder to classify them with our current historiographical categories. We hope that our volume will open new discussions about such categories and will encourage the exploration of other branches of Cartesian philosophy.

Different concepts of the microscope in the 1660s

A guest post by Ian Lawson from the University of Sydney.

Ian Lawson writes…

Margaret Cavendish’s Observations upon Experimental Philosophy (1666) was a direct criticism of the Royal Society, largely focused on their most prolific work to that date – Robert Hooke’s Micrographia (1665). Cavendish was no fan of experimental philosophy generally, thinking it likely to lead to civil strife, and needing in any case to be guided by speculative thought, she criticised microscopes specifically for a few particular reasons:

  • They’re difficult to make and use;
  • They’re not very useful (Cavendish asks if observing a louse through a microscope can prevent it from biting); and, relatedly
  • They distort nature.

This last, I would like to suggest, points to a different way of understanding and conceptualising the instrument to that of the Society microscopists (I am thinking particularly of John Wilkins, Christopher Wren, and Hooke).

Cavendish writes:

    I do not say, that no glass presents the true picture of an object: but only that magnifying, multiplying, and the like optic glasses, may, and do oftentimes present falsely the picture of an exterior object; I say, the picture, because it is not the real body of the object which the glass presents (pp. 50-51).

A louse, viewed under the microscope, looks like a lobster, and a sharp knife looks blunt. “[I]f the edge of a knife or the point of a needle were naturally and really so as the microscope presents them, they would never be so useful as they are” (p. 51). This is of course a direct reference to Hooke – a needle and a razor were the first two observations in his Micrographia.

Hooke's drawing of the edge of a razor

Hooke likewise admits that if the razor were “really such as it appear’d through the Microscope, it would scarcely have serv’d to cleave wood, much less to have cut the hair of beards.” Unless, he continues, it were used

    after the manner Lucien merrily relates Charon to have made use of, when with a Carpenter’s Axe he chop’d off the beard of a sage Philosopher, whose gravity he very cautiously fear’d would indanger the oversetting of his Wherry (p. 5).

Hooke’s razor, though lacking a knife’s sharp edge, still has the capacity to rob a philosopher of his wisdom, by showing intuitive assumptions are unfounded. Cavendish appears to suggest there is one scale that an object exists ‘naturally’ at. On the other hand Hooke, Wilkins, and Wren emphasise the contingency of human senses:

    [I]f there were another Species of Intelligent Creatures in the World, they might have quite another kind of Apprehension of the same thing, and neither [theirs nor ours] perhaps as they ought to be.

(Hooke, General Scheme, or Idea of the Present State of Natural Philosophy, p. 8)

The Royal Society microscopists didn’t so much see themselves as altering the objects they were looking at, but rather modifying their own senses. They enter the micro-world, and present the razor as it would seem to someone the size of an insect. It may not retain its traditional use at this scale, but it is the observer who has been distorted rather than the object.

I’m not really sure how illustrative a difference this is to point out, but my feeling is it is tied in with a number of related themes and can possibly help to shed light on them: optimism for the new optical technologies; the new optics of Kepler and Descartes and the naturalisation of vision; experimental as opposed to mechanical philosophy; and Hooke’s approach to instruments more generally.