A few questions

Latin Learning Latin
1

Hello all,
It has been a while since I posted, but I am glad to be back.

I am working on a document by Alhazen (aka Ibn al-Haytham), who is describing experiments/experiences with vision and refuting the “emmision theory” that proposed that vision was produced by the eye emitting rays towards the object. He describes staring at a strong light source, closing the eyes or looking at a dark location and the image of the light source persists.
The source I am using states that visum should be understood to be “the eyes.”

I have some questions on certain points. Here is the text for my first three questions, specifics in bold.

Et invenimus iterum quod, quando aspiciens inspexerit viridarium multae spissitudinis herbarum, super quod oriebatur lux solis: et moretur in aspiciendo ipsum: deinde convertat suum visum ad locum obscurum: inveniet in illo loco obscuro formam coloratam a virore illarum herbarum: diende si aspexerit in ista dispositione visiblia alba: et fuerit illa visibilia in umbra, et loco debilis lucis: … et si clauserit oculum suum: iterum inveniet in ipso formam lucis et formam viroris: deinde discooperietur illud, et auferetur.

My questions are:

  1. in illo loco obscuro - Sometimes in loco means “replacement/substitute”. Is that the same sense here, or is it simply “in that dark location”?
  2. in ista dispositione visiblia alba – I am at a loss here. Is it all one phrase as “in that white visible arrangement”? Or something else?
  3. Illud – to what does this refer? It is neuter but the nouns in the previous phrases are not neuter.
  4. visiblia alba also occurs later: deinde auferat visum suum ad visiblia alba in loco debilis lucis. What does ad visiblia alba refer to here? visiblia alba are both adjectives.
  5. And earlier, he writes: Et similiter quando aspiciens fuerit in domo, in qua fuerit formam amplum discoopertum ad coelum: … Does in domo mean at home/house or in a room or something else?

This was a fun exercise as he describes clearly what one actually experiences and states “the illuminated colors work on the eyes.”

Thanks for any help.

2

The “emission” theory is clearly implied in archaic Greek poetry. The object seen (e.g. a girl) is regarded as the recipient of rays (αυγαί, radii) emanating from the eyes of the beholder. Lucretius’ theory was different (Epicurean: εἴδωλα/simulacra).

As to visum, I guess in English we would say he turns his “eyes” but the Latin says convertat suum visum, he turns his look, his gaze.

I’ll leave your specific questions to others (but in the first it’s just “in that dark place,” and in 2 the visibilia alba are the object of aspexerit—then should fuerit be fuerint? all part of the si clause).

3

mwh,

Thanks for the emission theory expansion. Great background.

Regarding fuerit, my commentary states: “fuerit can serve both as the future perfect indicative and as the perfect subjunctive” without further explanation. There are many other verbs in the text that could be in either of these tenses. I suppose the idea would be to be consistent in the choice for translation.

Thanks for your always helpful comments.

4

Opps, I lost track of visibilia alba.
I took those two adjectives as ablative and no possibility of being the object of aspexerit, even as substantives.
Does aspicio take ablative in some situations? And change meaning? I couldn’t find that usage.

5

While alba could theoretically be an ablative (but is accusative neuter here), visibilis, e is a third declension adjective, so the form visibilia cannot be an ablative.

6

Laurentius,

Thanks for the clarification. I got caught up trying to connect those adjectives with dispositione, that I neglected to look at alternatives. And missed visibilis -e altogether!

Your help is appreciated.

And apologies to mwh for missing his point on this.