Reflection and Polarization

One topic neglected in phenomenology is the polarization of light and the results for reflection on the surface of water.

Heidegger may have known how Etienne Louis Malus was caught up in history.  It may be that prior to his experiments, Malus simply looked through the calcite and rotated it. [What did Heidegger know about setting a plow share?  Sharpening a plow share?]

Is a simple crystal rotation and the unexpected result prey to the Heideggerian attack on numbers? [cf Groups and Category theory]  Rotation here is not in number of degrees, but "turn on end in the same plane".

This might have been an example to put before Heidegger at Davos.  He tells Elfride that he spoke for 90 minutes without notes.  But his opponent, Cassirer, was known for his remarkable memory.

Malus does emerge with his law, but in his lifetime there will be no suitable glass manufactured.  Did Heidegger know anything of the role of types of glass in the advance of astronomy?  What if fine glass had been a Swabian speciality?  Or would Heidegger have avoided this topic as coming to close to acknowledging Spinoza?  But the problem with glass led to Malus being all but forgotten.

What are we to believe Heidegger knew about the history of science?

We do not mock Herschel for imagining the sun spots to be habitations or life on the sun.  He contributed too much to be mocked - unless he suppressed contributions by his sister.

Mercury is best viewed with magification using a suitable filter - depending somewhat on the glass of the objective lens or the quality of the mirror.  Was Heidegger aware that Mercury is somewhat different viewed in a refractor from Mercury viewed in a reflector?  If asked if stars appear "larger" under 200x magnification than under 20x magnification would he have replied "If course!  Mere boys know that!"  Why does Mars not look like red Antares or red Betelgeuse or another large red star at 20x yet easily mistaken at 2x magnification?  What are we to imagine his response might be compared to that of Husserl (who began in astronomy)?

To what extent was Heidegger's view of "calculating" science a result of simple ignorance (he never sat the science and math exams after leaving theology) ?  Was it not the case with regard to the German Volk that he utterly discounted both liberalism and economics as much as he rejected civil law and precedent?  Did he ever read any economics other than a little Marx?

More importantly: was his analysis of tools adequate to the rotating calcite example? Variant: is it adequate for using Iceland Spar for daytime navigation at sea or even for orienteering without compass in the South German Hills?

Q: which of Heidegger's favoured students had a background in science?  Compare Reinach and law.
see: Iceland Spar
note: Recent Habermas on international law: compare post-1933 Gerhart Husserl and E.Cassirer
idle query: Heidegger's "fontane" was a hand water pump on a well - or was it in fact mounted on a "source" ?  cf Leibniz and the mineshafts

Sameness and difference: Heraclitus and Heidegger on the daily sunrise: the rising of the sun or the return of daylight?  And if the sun one day rose in the "west" - would the hiking Heidegger change his direction?  If so, why so?