Frames /sing

kvond

Tag Archives: Lens

Heine on Spinoza: Undulating Forest of Thought

I never really fully grasped the source of Negri’s political enthusiasm for Spinoza until I started looking at Heine, Heine who was inspired by the revolutionary potential Spinoza unleashed in terms of the Pantheism Controversy. Heine saw in Spinoza’s reclamation of matter as divine just what was lacking in Hegel’s turn to Idea and Spirit. And in this as well, an invocation of the proto, pantheistic, pre-Christian Teutonic religions of the earth.

This quote captures some of that pristine and material beauty, the way-point between both Plato and Aristotle. For those who find Spinoza utterly dry, they perhaps suggest an eruptive potential not always easily glimpsed. And one can see as well the “top” and “bottom” tension that Negri argues for as well.

“[With Spinoza] we become conscious of a feeling such as pervades us at the sight of great Nature in her most life‐like state of repose; we behold a forest of heaven-reaching thoughts whose blossoming topmost boughs are tossing like waves of the sea, whilst their immovable stems are rooted in the eternal earth. There is a peculiar, indescribable fragrance about the writings of Spinoza. We seem to breathe in them the air of the future.”

“Religion and Philosophy in Germany: A Fragment”

He says important, interesting things about the ownership of ideas as well and the possibilities of transforming Spinoza’s thinking beyond its argumentative form. Not to mention, here is the earliest comparison of his philosophy to a lens, and his lens-grinding that I have run across.

“Nothing is more absurd than ownership claimed for ideas. Hegel did, to be sure, use many of Schelling’s ideas for his philosophy, but Mr. Schelling would never have known what to do with these ideas anyway. He always just philosophized, but was never able to produce a philosophy. And besides, one could certainly maintain that Mr. Schelling borrowed more from Spinoza than Hegel borrowed from Schelling. If Spinoza is some day liberated from his rigid, antiquated Cartesian, mathematical form and made accessible to a large public, we shall perhaps see that he, more than any other, might complain about the theft of ideas. All our present‑day philosophers, possibly without knowing it, look through glasses that Baruch Spinoza ground.”

Advertisements

Spinoza’s Optical Letters: Redux

As some know, primarily last summer I spent my time researching and theorizing on Spinoza’s lensgrinding and optical concepts, a largely underdeveloped field in Spinoza studies. The greater portions of my findings are listed here on this site under the sub-heading Spinoza’s Foci. A spearpoint of this research was uncovering the substantive arguments and conceptions that lay behind Spinoza’s rejection of Descartes’ optics, as found in his two letters 39 and 40, letters that have be nearly completely ignored by commentators on Spinoza, or if address, addressed in what seems a delinquent, or dismissive fashion. Spinoza is mostly thought to not know what he is talking about. On the other hand, Spinoza’s objections if carefully examined reveal both technically an alternate position on the problem of “spherical aberration,” but more deeply, a radically distinct conception of what vision is, in particular how it works as an insufficient analogy for consciousness. While Descartes wanted to emphasize the power of the central clarity powers of hyperbolic vision (both in the human eye, and in his proposed lenses), Spinoza understood vision and conciousness both as holistic events, ones best approached with the pragamatic appreciation of our limitations. I provide very little philosophical extrapolation here, though the implications are vast, perhaps running through down to the root of Idealism and Phenomenology. This epistolary commentary also does not touch on such other important factors such as the kind of lathe Spinoza likely used, nor much on his likely technique, and kinds of instruments he made and calculated for, which form a significant secondary branch of my research. Yet as these letters remain nearly the only first hand statement Spinoza made on optical matters, they are the anchorage point for anything else that is likely to be asserted.

For the convience of interested readers I here post a Word document version of my line-by-line explication of these rarely read and rather under-interpreted letters. I realized that the previous weblog versions were very difficult to read and browse through, hopefully something this version will correct. The two entries that can be found in this document are: Deciphering Spinoza’s Optical Letters and  Spinoza: Letter 40 and Letter 39. These are both the English translation of the two letters by Spinoza, and then my explication. This version is not footnoted (though there are citations), and it retains some of the idiocyncratic paragraphing and color coding. It is a 14,000 word document (48 pages), though Spinoza’s letters are only 900 words or so.

[click download]: Deciphering Spinoza’s Optical Letters Line by Line

Constantijn Huygens Uses Spinoza’s Grinding Dish (1687)

In correspondence Wim Klever directs my attention to evidence that the Huygenses used Spinoza’s grinding equipment as late as 10 years after his death. The citation is here, thus translated from the OCCH:

[I] have ground a glass of 42 feet at one side in the dish of Spinoza’s clear and bright in 1 hour, without once taking it from the dish in order to inspect it, so that I had no scratches on that side ” (Oeuvres completes vol. XXII, p. 732, footnote).

If I have the details here correct, it seems either that indeed the Huygenses had purchased Spinoza’s lens grinding equipment at auction in November of 1677 and maintained the use of that equipment, or that Spinoza may have made a grinding-dish for the brothers under their specification before he died. What is revealed is that Spinoza’s skill had been directed toward not only microscope instruments, but also towards telescopes of a rather large magnitude. This lens appears to have a focal length of 42 ft. And secondly of course, here Constantijn jr., a rather experienced lens-grinder himself, seems to have marveled at the confidence in the lumininocity of the lens produced.

(This reported Spinoza lens is much shorter in focal length than three known to have been made in 1686 by Constantijn: w/ diameters 195, 210 and 230 mm, and w/ focal lengths of 122, 170 and 210 ft.; each “made from the same very poor glass – a heterogeneous and discoloured potash-rich, but essentially lead-free `forest glass’.”)

 

A Conflation of Spinoza Diagrams

How Spinoza Thought of the Eye, the Lens and The Modes

Perhaps this is an irresponsible and trite comparison, but sometimes the mind indeed works visually, even in authors as exacting and deductive as Spinoza attempts to be. It is striking that Spinoza uses two very similar diagrams to illustrate on the hand, the powers of spherical lenses to most ideally focus rays across an infinity of axes, (the manifestation of which is subject to the properties of real lenses):

Text not available

Letter 39 to Jelles, March 3rd 1667
Benedicti de Spinoza opera quotquot reperta sunt quotquot reperta sunt By Benedictus de Spinoza, Baruch Spinoza, Johannes van Vloten, Jan Pieter Nicolaas Land

Depicted above are the hypothetical intersection of rays, in two sets taken to be parallel, as they arrive at the surface of a spherical lens. Such rays are taken to be then focused at the back of the circumfrance, as the would be at the back of the eye, or as part of the refractions of a lens.

 

In this diagram, Spinoza illustrates how each contingently expressive mode – what is usually taken to have come into existence and then will pass away – are implied by, that is caused by as immanent to, the Idea of an infinity of points that make up a circle. In this way, the rectangles that are immanent to a circle’s circumfence are by analogy seen to be dependent upon that circle. The rectangles come and go, the circle remains eternal. As explained in Ethics IIp8s:

The nature of a circle is such that if any number of straight lines intersect within it, the rectangles formed by their segments will be equal to one another; thus, infinite equal rectangles are contained in a circle. Yet none of these rectangles can be said to exist, except in so far as the circle exists; nor can the idea of any of these rectangles be said to exist, except in so far as they are comprehended in the idea of the circle.

There is the simple coincidence of using a circle to diagram both physical effects, and metaphysical effects (which for Spinoza are of course commensurate). But if one allows a conflation, one that may have occurred within Spinoza’s thinking, in the first we have the effects what occur within the eye, as it interacts with events outside of it, and in the second, we have the effects (modes) as expressed immanent to the circle that contains them.

Because Adequate Ideas are understood by Spinoza to be Ideas uncaused by something external to them, I don’t think it is too big of a leap to understand that when Spinoza is diagramming the effects of light with the eye (and for a lens, post-angle of incidence), he is thinkingof the second diagram. It is perhaps for this reason that Spinoza is not obsessed with the crystality of vision that occupied Descartes in his quest for the hyperbolic lens. The sharpness of an image is but a part played in an assemblage of knowledge. However clearly one’s eye, or lenses work, this simply is not clear thinking. Of course Descartes understood this as well, but there is something to how Descartes and Spinoza each responded to spherical aberration which reveals a difference of emphasis in the very project of mental and physical liberation. I believe in this co-incidence of diagrams, a profound conflation is being accomplished in Spinoza’s process of thinking.

I see hear as well an interesting graphic subsumption of the scattering of rays that occur with spherical aberration, as in being focused they tend about a “mechanical point” [Johannes Hudde]. Much as rays are never entirely focused to a mathematical point (even with real, hyperbolic lenses), so too we never possess wholly adequate ideas. The focus rays as seen in the first diagram (again, if we allow an analogical thought), appear to enact indices found in the second diagram. Is Spinoza at some level conceiving of rays of focus as being parallel to the adequacy of ideas? And is Spinoza’s theoretical acceptance of spherical aberration [a la Hudde] a product of his acceptance of the fundamentally inadequate nature of ideas we hold? Is his mechanical project of lens focusing analogous to a mechanical – that is, pragmatic, rational and crafted – construction of human freedom? These are large and obscured questions.

This certainly does not make up an argument either for Spinoza’s position, or for an interpretation of Spinoza’s position. It is really more an intuition into the kinds of thought processes Spinoza may have been engaged in, in part elicited by the diagrams he used to make things clear. Meant is a direction for future analysis.