Francis Bacon’s typology of pneumatic substances

For Bacon, spirit in general is a “breath compounded of an airy and a flamy substance” (OFB VI 321). One extreme is that of the air (rather cold and inactive), the other that of fire. But the mixture of air and fire is not mechanical (OFB XII 355); it is a complete mixture (which cannot be simply evaluated in terms of more air/less fire; or more fire/less air, but has a ‘mysterious’ character, OFB XII 352, 376 etc.). In between ‘air’ and ‘fire,’ we have a whole range of spirits: the non-living ones “are nearly consubstantial to air,” while the “vital spirits come closer to the substance of fire.”(OFB XII 354-5) One fundamental principle in Bacon’ natural philosophy is that there is no tangible body devoid of spirit. By contrast, spirits can be ‘free’ or ‘enclosed’ in matter. Meanwhile, spirits also come in all sorts of shapes and forms: and although Bacon sometimes attempted classifications of pneumaticals (i.e. according to their rarity in HDR) it is clear that their diversity resist any form of unique classification.

In the late natural histories, one can find series of experiments which seem to attempt to classify pneumaticals according to their properties. In some cases, the classification takes into consideration observational properties of pneumatics (hence, the resulting ‘classification’ will be called ‘phenomenological’). In some other cases, (esp. Sylva) the principle of classification seem to be the prevailing process (i.e. physical classifications). There is arguably also an attempt to divide spirits and matter in metaphysical terms.

It is not only that these classifications are not unique, they are also overlapping. However, the recurrence of such attempts to classify spirits in the late natural history seem to signify that Bacon was persuaded of the importance of achieving some form of classification, or typology of pneumatic substance.

Meanwhile, Sylva constantly insists on the diversity of spirits and the diversity of properties characterizing spirits. Spirits are “nothing else but a natural body, rarefied to a proportion, and included in tangible parts of bodies;” in addition, they are many differences between spirits: “they be no less differing one from the other than the dense or tangible parts.”(SEH II 381)

Phenomenological classifications

  1. Classification of spirits according to their rarity (HDR)
  2. Classification of spirits according to their heat (sources of heat, how the heat is processed…) (OFB XII 359)

Close distillation (forcing matter/spirit to react to heat in a close container) (SS I 99), and other experiments with closed containers destined to mix air and flame or watery and oily

  1. Classification of spirits according to the qualities of the mixture of air and flamy (which gives it empirical characteristics such as “greediness,” “lassitude” …).

Physical classifications

  1. Classification according to the organization of spirit in matter (branched, cells, cut-off)
  2. Classification according to the even/uneven distribution of spirit in matter and the fineness of the spirit AND/OR strenght[1]
  3. Classification according to the processes that gets activated

Spirits are said to be the causes of all processes (SS I 98) (but whether a process or another takes over is also a property of spiritual substance?)

Classification in terms of activity (resulting from the activated appetites)

[1] Spirits “weak” “clinging loosely, … practically consubstantial with plain air,” “dwelling mainly the outer parts of the body.;” “transient guests” in bodies – Versus spirits “stronger,” “further inside,” “submerged and buried deeper in the solid parts of the thin.” (OFB VI 291) Also, there is a rule in HVM which links the even/non-even distribution of the spirit with its properties/activity – abundance of spirit non-evenly distributed makes the spirit more predatory OFB XII 361.

Metaphysical classification (?)

Spiritus vitalis/Spiritus mortualis (HVM, OFB XII 351)

(Also: (DVM OFB VI 352-3) – vital spirit, peculiar to living things OFB VI 357 – differs from the other spirits not only because it is differently organized, but because it has an inner warmth and because it feeds upon “the moist parts and joice of the living body” (OFB VI 359))

HVM: Rule/Canon IV: In all living things there are two kinds of spirits: non-living ones (Mortuales) of the kind found in inanimate substances, and the superadded vital spirits.

Vital spirit is something different from all the spirits that exist in inanimate bodies because: it needs aliment, it is somehow closely connected with the body (being ‘in charge’ of the body and all the other spirits), it ‘rules’ the other spirits and the body.

Thus we should know that there exist in flesh, bones, membranes, organs, and every single part of the human body, spirits which pervade them while they live, and which are identical to those which exist in those parts – flesh, bone, membrane and the rest – when they are separate and dead, and identical to the ones remaining in the corpse. But the vital spirit, though it rules and has some consent with them, is very different from them, as it is integral and self-consistent [integralis, & per se Constans]. Now the non-living and vital spirits differ in two main ways: the first is that the non-living spirits are not in the least self-continuous, but are as it were cut off and surrounded by the grosser body which intercepts them rather as air is intermixed in snow or froth. But all vital spirit is self-continuous through certain channels which it pervade, without being completely intercepted. This spirit too is of two kinds: the one is just branched and runs through little thead-like tubes [Ducturs, & tanquam Lineas]’ the other has in addition a cell [Cellam] so that it is not just self-continous but is also gathered together in some hollow space and, relative to the body, in an appreciable quantity; and in this cell is the source of the rivulets which go their separate ways from there. This cell is mainly in the cerebral ventricles, which in humbler creatures are narrow, such that the spirits seem to be diffused through the whole body rather than concentrated in cells, as we see in snakes, eels, and flies whose individual parts still move after being cut away. (OFB XII 351-353)

Although Bacon attempts to reduce this fundamental difference to physical and phenomenological differences, it is not entirely clear that this is a successful enterprise (or an enterprise that can succeed). In principle, the differences are:

  • Of organization (non-living spirits are cut off and not organized) and distribution (within the body; how well distributed are the vein, how far away from the cells etc. see DVM)
  • Of composition (all spirits are a mixture of air and flame, and the living one are closer to the nature of flame, but Bacon emphasizes that this is not a mechanical mixture and hence “when this rule states that vital spirits come closed to the substance of flame, it must be taken to mean that they do so more than the non-living ones, and not that they are more flamy than airy” (OFB XII 355).
  • Of behavior/appetites (the non-living spirits have two appetites/desires – to multiply, and to fly and meet with connaturals; living spirits have more appetites, for example they are “absolutely terrified of leaving its body” – which means that living spirits are “principal” spirits of bodies and they are metaphysically united with their bodies)
  • Of heat/warmth (OFB VI 357)

Another major difference is said that non-living bodies/spirit do not need aliment, while the others do (but, however, spirits in inanimate bodies ‘eat-up’ matter)

DVM: But it is unquestionably the case that among the difference of the spirit there are two in particular which have the greatest importance: for spirits differ in body or in force, for we find that some are more biting, lively and robust while others are duller and weaker. And that very force proceeds either from the nature of the thing, or from the length of time that has elapsed since the death of the body. Alternatively, spirits vary in fraction or comminution, for we find bodies in which the spirtis are more diffused and dispersed so that the portion of spirit in any given part is less than it might be, but other bodies in which the spirts have more space and larger concentrations. But again, we find that the distribution of spirits with reference to their sites is more uniform in certain bodies so that the spirits are diffused more evenly in particular parts of the body; but in other bodies they are distributed less evenly so that the residences of the spirit are more spacious in one place and more confined and circumscribed in another. (OFB VI 282-3)

 

Hypothesis 1: As with many of his new concepts, Bacon seems to use “spirits” in more than one way; using a range of traditional, loose meanings (spirits are the breath of life, they are the source of activity in the Universe and they originate “in the stars,” there are living spirits and non-living spirits etc.) and a more specific, technical meaning (a class of material substances characterized by rarity, heat (potential or actual heat), active powers, the capacity to diffuse at considerable distances, and other several properties such as greed which Bacon attempts to express in terms of combinations of attributes).

Hypothesis 2: There are small but significant differences between DVM and HVM on the one side and SS on the other regarding the fundamental and derivative properties of pneumaticals. These differences can originate in the fact that in SS Bacon asks different questions and is interested in different aspects of the workings of spirits than in the other two works. Thus, there is no equivalent of spiritus mortualis at work. Meanwhile, there seem to be a distinction between the principal spirit of a body and other spirits which might (or might not) inhabit the same body. The principal spirit can be the living spirit of DVM and HDR. Meanwhile, there clearly are other organized spirits at work in the same body (a scion grafted on a stock poses this problem of two principal spirits ‘fighting’ and one is overcoming the other).

Sylva Sylvarum has a number of experiments which seem to be saying that there is no metaphysical distinction between vital spirits and the others, that there is indeed a merely variation in the mixture of air and flame at work, and that one can simply vary the proportion of the two in the mixture

SS1.30 “although air and flame being free will not well mingle; yet bout in by a body that hath some fixing, they will. For that you may best see in those two bodies (which are their aliments) water and oil; for they likewise will not well mingle of themselves, but in the bodies of plants and living creatures they will.”

A Cartesian challenge to the early modern philosophy of experiment

Much has been written about seventeenth-century experiments and experimental philosophy. My paper for the CELFIS seminar of October 8 aimed at engaging with that tradition. In particular, I was concerned with the recent discussion by Peter Anstey of the so called BBH model of the experimental philosophy (BBH stands for the name of Bacon, Boyle, and Hooke). As a reaction to Thomas Kuhn and Peter Dear, Peter Anstey’s article provides a very nice introduction into the Baconian experimentation and its main developments in the second half of the seventeenth century. Both Boyle and Hooke engage with a form of experimentation that is labelled here “Baconian.” It is not, however, the purpose of this small blog post to engage with the details of Anstey’s article, but rather to try to complement his analysis with a new example of experimentalism that can be found in a completely different source. This is the case of the experimental work of the Cartesian natural philosopher, Jacques Rohault.

In my lecture, I’ve referred to two experiments that were performed by Rohault: with pneumatic devices, on the one hand, and with glass drops, on the other hand. It is well known that Boyle was the main contributor to the pneumatic or baroscopic experiments of the 1660s. Hooke was among the first to examine glass drops and to provide an explanation for both the production of the small glass objects and for the curious phenomena produced by those. Interestingly, Rohault deals with both of these issues in experimental terms.

Now, one might very well wonder why is important that a Cartesian philosopher was providing an explanation for some intriguing experiments; after all, he is a Cartesian, therefore a speculative philosopher (see the Otago blog here and here), and he would explain all phenomena according to the principles of Cartesian physics. Yet, this classification of seventeenth-century philosophers into “experimental” and “speculative” should not be an impediment in searching for explanations in one’s writings. But there is more than that and I argued in my paper that it is precisely Rohault’s experimental approach to the study of the two phenomena that would make difficult to draw a clear boundary between his work and the works of the most representative experimenters of the BBH model.

I have argued elsewhere that Rohault treats the study of the properties of the air in experimental terms. He does not simply jump from the conclusions derived in the general part of Cartesian physics (which is most often claimed that he does), but actively engage in experiments and observations.

With respect to the study of glass drops, Rohault is also concerned to perform all the needed observations before providing an explanation. This is also what Hooke did in his Micrographia.

As a tentative conclusion for this very sketchy blog-post, I claim that based on these two experiments, Rohault should be placed in the same context with Boyle and Hooke, so as a representative of the BBH model. If, on the contrary, one would like to point to his “Cartesianism,” then, one simply overlooks his experiments and this would raise new worries for the use of historical categories: if one dismisses some experimental practices only on the basis of placing the practitioner to one or another camp, then, the problem is not any more with the use of experiment in natural philosophy, but with the way various natural philosophies of the period were classified in our histories.

Francis Bacon and the use of measurement in experiments


One central component of experimental philosophy is measurement. Various properties, quantities, degrees and qualities were counted and measured with more or less exactitude starting with the early modern period (see for example, the analysis of temperature measurement in A.Borrelli, “The weatherglass and its observers in the early seventeenth century”, in: Claus Zittel, Gisela Engel, Nicole C. Karafyllis and Romano Nanni (eds.), Philosophies of technology: Francis Bacon and its contemporaries, vol. 1 (Leiden: Brill, 2008) 67-130 (Intersections 11/1)). Seen in itself, measurement was almost universally considered a tool meant to improve knowledge and to give strength to different arguments and to rebut others. This attitude was shared by Francis Bacon too, as I briefly attempted to show in a small presentation I have made for the 4th Bucharest Colloquium in Early Modern Science. One can infer this from the following example taken from Bacon’s Sylva Sylvarum:

“It is strange how the ancients took up experiments upon credit, and yet did build great matters upon them. The observation of some of the best of them, delivered confidently, is, that a vessel filled with ashes will receive the like quantity of water that it would have done if it had been empty. But this is utterly untrue; for the water will not go in by a fifth part. And I suppose that that fifth part is the difference of the lying close or open of the ashes…” (Sylva Sylvarum, SEH 34).

There are many other examples of experiments in which Bacon used to invoke the measurement and counting of quantities in order to champion his ideas (see for instance, entries 1, 19, 21, 32, 33, 46, 59, 60, 76, 88, 104-110, 156, 159, 248, 306, 307, 309, 310, 318, 324, 363 etc, to give just few examples taken from the first three centuries of Sylva). Here are two more extended examples:

“Dig a pit upon the sea-shore, somewhat above the high-water mark, and sink it as deep as the low-water mark; and as the tide cometh in, it will fill with water, fresh and potable… I remember to have read that trial hath been made of salt water passed through earth, through ten vessels one within another, and yet it hath not lost his saltness, as to become potable: but the same man saith, that (…) salt water drained through twenty vessels hath become fresh… But it is worth the note, how poor the imitations of nature are in common course of experiments, except they be led by great judgment, and some good light of axioms. For first, there is no small difference between a passage of water through twenty small vessels, and through such a distance as between the low-water and high-water mark…” (Sylva Sylvarum, SEH 1-2)

 

“The continuance of flame, according unto the diversity of the body inflamed, and other circumstances, is worthy the inquiry; chiefly, for that though flame be (almost) of a momentary lasting, yet it receiveth the more and the less: we will first therefore speak (at large) of bodies inflamed wholly and immediately, without any wick to help the inflammation. A spoonful of spirit of wine, a little heated, was taken, and it burnt as long as came to one hundred and sixteen pulses. The same quantity of spirit of wine mixed with the sixth part of a spoonful of nitre, burnt but to the space of ninety-four pulses. Mixed with the like quantity of bay-salt, eighty-three pulses. Mixed with the like quantity of gunpowder, which dissolved into black water, one hundred and ten pulses. A cube or pellet of yellow wax was taken, as much as half the spirit of wine, and set in the midst, and it burnt only to the space of eighty-seven pulses. Mixed with the sixth part of a spoonful of milk, it burnt to the space of one hundred pulses. Mixed with the sixth part of a spoonful of water, it burnt to the space of eighty-six pulses… So that the spirit of wine simple endured the longest; and the spirit of wine with the bay-salt, and the equal quantity of water, were the shortest.” (Sylva Sylvarum, SEH 366)

I propose the following table as a tool for a concise representation of Bacon’s measurement of the continuance of flame:

  • Spirit of wine = 116 pulses
  • Spirit of wine + 1/6 nitre = 94 pulses
  • Spirit of wine + 1/6 bay-salt = 83 pulses
  • Spirit of wine + 1/6 gunpowder = 110 pulses
  • Cube of yellow wax + ½ spirit of wine = 87 pulses
  •  Cube of yellow wax + wine + 1/6milk = 100 pulses
  • Cube of yellow wax + wine + 1/6 water = 86 pulses

 

This raises a plenty of interesting questions dealing with the way Bacon uses measurement that is worth to be discussed. Here is a tentative list with few of them:

–          What type of measurements does Bacon employ?

–          What type of quantities or qualities is subjected to measurement by Bacon?

–          What other examples of Bacon’s measurements can be represented by such tables?

–          In what theoretical cases is measurement invoked?

–          How important is the exactitude in the measurements?

–          When does measurement help in constructing an argument and when does it help in rejecting other’s arguments?

–          Is measurement an effective tool in building up the theory of matter?

–          Is measurement used independently of Bacon’s theory of matter?

The examples of measurements Sylva Sylvarum presents can be a good starting point for the discussion of these points. Different answers to these questions can also set the stage for a comparative analysis between Bacon’s use of measurement and other philosophical treatments of it.

We would love to hear your comments, suggestions and thoughts on these matters, so please leave us a comment.

On the reception of Bacon’s views in 1625

A while ago, in the Scientiae 2013 conference-panel on “Francis Bacon’s Art of Discovery: origins and development,” I’ve raised the problem of talking about “Baconianism” in the second half of the seventeenth century. The context discussed in that paper was that of the French Cartesianism, a very implausible source for such a discussion, if we are taking seriously the traditional stories about the seventeenth-century thought. The cases discussed in that paper – Nicolas Poisson, François Bayle (via Samuel de Fermat), and Descartes himself – reveal an interesting approach to “Baconianism,” which I would like to complement in this blog-post with several new questions. More recently, in a panel-discussion at the 4th Bucharest Colloquium in Early Modern Science, I’ve asked some questions about Mersenne’s early reception of Bacon’s views on method.

In 1625, Marin Mersenne published his treatise on La Vérité des sciences, which, in the ch. 16 of Book 1 deals with Bacon’s method. From the text, Mersenne’s sources seem to be Bacon’s Great Instauration and The Advancement of Learning. Mersenne’s first objection to Bacon is that most of the things he says are not needed or insufficient. Mersenne explicitly refers to medicine as refuting Bacon’s views: “il se trompe en plusieurs choses, comme quelques excellens Medecins ont reamarqué, lors qu’il parle de la Medecine, & qu’il dit que l’histoire, & l’experience de plusieurs choses qu’il nomme, n’a point encore été faite” (p. 209).

Why would medicine come to represent such a clear evidence against Bacon’s views?

What kind of medicine is discussed here?

There are various objections raised by Mersenne to Bacon, but for this blog-post, I would like to point only to another passage, where he praises the Englishman’s experimental activity on/ with animals, vegetables, and different materials of alchemical use: “Ce que je trouverois bon en sa doctrine, est qu’on feît toutes sortes d’experiences pour découvrir comment les esprits des plantes, & des animaux exercent leurs operations: & leur multitude: comment & par quelle vertu les eaus Royalles, fortes, & toutes celles que l’Alchymie nous donne, dissolvent l’or, l’argent, le cuivre, l’étain, le fer, & les autres métaus, & mineraus: porquoy elles ne dissolvent pas le verre, les pierres, les plantes, &c.” (p. 211).

Why is Mersenne highlighting these aspects? Is this because Bacon picks up some experiments and practices from outside of the philosophical domain and adjusts them as proper philosophical problems?

If this means doing experiments on all sorts of materials, to which one has to try various operations – in other words, variation both within the materials involved and in the experimental procedures – something that has been done by other natural philosophers (and craftsmen) of the early modern period, then what makes it “Baconian”?

And as a final question, these passages seem to suggest that Bacon’s experimentalism says something to his seventeenth-century contemporaries when he talks about medical and alchemical problems. Why are these two disciplines receiving more emphasis in the reception of Bacon’s views rather than other philosophical disciplines?

We would love to hear your comments, suggestions and thoughts on these matters, so please leave us a comment.