Some Observations on Spinoza’s Sight

How The Two Philosophers “See” I feel that there are some important things to say about my recent post, A Diversity of Sight: Descartes vs. Spinoza , but I am still undecided just how deep the influence of these thoughts run. So pervasive is the metaphor of vision and light within Western metaphysics, any identification of an [...]

A Possible Influence of Diamond Polishing on Assited Lens-grinding

  Was the horizontal grinding wheel, and the leaded-head a definitive influence upon the automatic conceptions of lens-grinding machines? Below are posted two notable examples of automatic designs, by Hooke and Hevelius, and the essential diamond-polishing design:  Hooke, first plate Micrographia (1665)     Hevelius, Machina Coelestis, after page 433 (1673)       Jan [...]

Spinoza and Diamond Polishing?

What was Spinoza’s Relationship to the Gem and Diamond Trade I post here a portion of a hard to find book, in the interest of establishing a baseline of information for others. Because this site has involved a variety of hypotheses on the kinds of influences Spinoza may have had, all should be sketched out [...]

A Diversity of Sight: Descartes vs. Spinoza

Different Foci of “Clear and Distinct” This may be premature in my process, but I would like to set down some simple correspondences that have arisen in my reading of Kepler’s Paralipomena to Witelo (1604), correspondences that elicit strong tidal differences between Descartes’ approach to vision – with its attendant metaphysical counterpart, the clear and [...]

An origin of Spinoza’s “cones of rays” explanation, Letter 40

[addendum: in addition to these thoughts, the influence of a more recent source, James Gregory's Optica Promota (1663) has to be considered] Kepler and How Spinoza Viewed the Eye and Light As a point of reference it is important to locate the origin of Spinoza’s phrase “cones of rays” found in his letter 40, since [...]

Descartes’ 8th Rule: A Spinoza Touchstone

Rules For the Direction of the Mind, gives clue to Spinoza’s concept of the instrumentation of knowledge I post here Descartes’ 8th Rule from his Regulae, as a marker to important influences upon both Spinoza’s philosophy in general – it contains the seeds of his argument for Three Knowledges, for instance – and his approach [...]

The Simple Microscope in the Hands of Van Leeuwenhoek and Huygens

Spinoza’s Microscopology: a prospective comparison of context It strikes me that there is a subtle, yet important contrast between the single lens microscope that Christiaan Huygens ended up offering by the Fall of 1678 and the design which was consistently used by Van Leeuwenhoek, a contrast that points up a branching out of conception of the relationship between instrument [...]

Some Rough Thoughts On Spinoza and Technology

The Free Hand Today, in contemplating Spinoza’s objection to Huygens’s semi-automated lens-grinding lathe (from Letter 32), and considering what it might mean for an overall Spinoza view of technology, I am struck by an immediate incongruity. Christiaan Huygens’s love of the mechanical, that is the ambition for the nearly direct implementation of the math to [...]

The Rijnsburg Lathe: Like the Sun, not 200 Feet Away

Mystery Solved: Rijnsburg Lathe, a 19th Century Woodturner’s Lathe Stan Verdult over at the excellent Spinoza site http://spinoza.blogse.nl/ has done excellent research and unearthed the origins of the Rijnsburg lathe, which for some reason the Spinozahuis seems to have been less than forward about. He has uncovered a 1984 Bulletin which tells us that H.G. van de Sande [...]

What Spinoza and Huygens Would Have Seen that Summer Night

Telescoping with Spinoza and Christiaan Huygens The night sky, 11:31 p.m. July 13th 1665 near Voorburg  …with which they have been able to observe the eclipses of Jupiter caused by the interposition of satellites, and also a kind of shadow on Saturn as if made by a ring. – Spinoza to Oldenburg, May 1665 It is [...]