In ספר הברית השלם, authored by פינחס אליהו בן מאיר הורביץ, he writes that there are akhronim who say that the sun possesses no heat (p. 50):

ושקר אמרו שהמה מורכבים מארבעה יסודות וגשמיים כמו עולם הזה, כי איך אפשר להיות בני-אדם כמונו יושבי חמה וחום השמש לא ישרוף אותם, וכל חום בצאן ובקר ויחיו? ואם אין חום בשמש, כדעת האחרונים, איך לא יעורו עיניהם מראות בתעצמות זוהר של המאור הגדול הזה תמיד, ואנו לא נוכל להביט בו רגע אחד? או איך אפשר להיות בני-אדם יושבי שבתאי ולפני קרתו מי יעמד?

Is there a source for this?

  • 1
    Hard to believe
    – Shmuel
    Commented Jul 26, 2023 at 17:46
  • I agree that it's difficult, yet seeing it written in a reputable book leads one to think...
    – Shababnik
    Commented Jul 26, 2023 at 17:52
  • וחם השמש ונמס Beshalach
    – Heshy
    Commented Jul 26, 2023 at 17:57
  • So how would you explain the phrase "אין חום בשמש"
    – Shababnik
    Commented Jul 26, 2023 at 18:18

1 Answer 1


This was a once extant view in the medieval era. In the Foundations of Modern Science in the Medieval Era (pp. 109-110) Edward Grant explains:

The celestial spheres, as we saw, were assumed to be composed of an incorruptible ether whose properties contrasted radically with those of the incessantly changing four elements of the terrestrial region. In Aristotle's scheme, change was unrealizable in the heavens because of an absence of contrary qualities, so that no pair of such qualities could act on the same celestial body or in the same portion of celestial ether. But if the heavenly ether lacked contrary qualities, why did natural philosophers and astrologers attribute contrary qualities to celestial bodies? For example, why did they describe Saturn as cold and dry, Mars as hot and dry, the Moon as cold and wet, and so on for the other planets? If these qualities were really absent from celestial bodies, why did astrologers and natural philosophers speak as if they were present? The standard medieval reply to such a question would have been that the celestial ether possesses these qualities only virtually (virtualiter), not formally (formaliter), or actually. That is, a celestial body is said to "possess" qualities like hotness or coldness only in the sense that it can somehow cause changes in the hotness or coldness in bodies below the Moon, even though that celestial body does not actually possess the qualities that it allegedly produces in terrestrial bodies. To say, for example, that Saturn is cold is not to say that the quality "coldness" actually inheres in Saturn's ethereal matter - indeed, it does not - but rather that Saturn has the capacity to produce the effect of coldness in the terrestrial region. Again, the Sun is not actually hot, but it has the capacity to cause hotness in objects in the terrestrial region.

This notion is similarly found in the Kuzari (4:3):

הַשֶּׁמֶשׁ – נִרְאֶה אוֹתָהּ עִגּוּל פָּשׁוּט כְּשִׁעוּר הַצִּנָּה וּבְתָאֳרָה: מַזְהִירָה, חַמָּה, נָחָה, וְהַשֵּׂכֶל גּוֹזֵר כִּי הוּא כַדּוּר גָּדוֹל מִכַּדּוּר הָאָרֶץ בְּמֵאָה וְשִׁשִּׁים וְשֵׁשׁ פְּעָמִים, וְשֶׁאֵינָהּ חַמָּה וְלֹא נָחָה, אַךְ הִיא מִתְנוֹעַעַת שְׁתֵּי תְנוּעוֹת מִתְהַפְּכוֹת

Another instance is offered by the sun, which we see as a round, flat body, resembling a shield and giving forth light and heat, being in repose. Reason considers it to be a globe a hundred and sixty-six times larger than the globe of the earth, neither hot nor immovable, but moving in two opposite directions...

The Ibn Ezra (Exodus 33:21) wrote:

ואל יעלה על לבך כי הארבעה תולדות הם בשמים. ויש חום בשמש וקור בלבנה ובשבתי חלילה חלילה כי הבריות העליונות נכבדות הן. ועליהם כתוב: כי הוא ציווה ונבראו ויעמידם לעד לעולם חוק נתן ולא יעבר.

Don't let it occur to you that the four elements [which are constantly subject to change] are to be found in the heavens. And that there is heat in the sun and coldness in the moon and Saturn, heaven forfend, for the celestial creations are glorious. And about them Scripture states "He hath also established them for ever and ever; He hath made a decree which shall not be transgressed."

Presumably R. Horowitz and any Aharonim he is citing are referring to this scientific model.

  • My only problem with this response is that rav horowitz mentions "אחרונים" which would imply other rabbis; as opposed to philosphers or scientists where I presume he would use a different language to refer to them.
    – Shababnik
    Commented Jul 27, 2023 at 23:11
  • I've updated my answer with a quote from the Kuzari and the Ibn Ezra. I assume that any later Aharonim are repeating this view that was already in circulation during the Rishonic era. I'll continue to update if I come across additional sources. Commented Jul 28, 2023 at 1:38
  • ThanQ. I appreciate your help
    – Shababnik
    Commented Jul 28, 2023 at 2:57

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