@AvrohomYitzchok asked me this question to support the assertions for another question: "Why don't newborns speak? Why do we need to learn a language?"

In my understanding, in Judaism, a soul is a complete entity having only one degree of freedom, namely the total amount of merits and sins. The soul is unchangeable otherwise in its other qualities. It dwells happily in the Treasure of souls until God decides to bestow it a chance of ascending to a better spot by coming down to this world and participating in the game of human history, getting rewards for observing Mitzvos and getting fouls for overriding it like in a video game, but the character itself stays unchanged through the game.

I also understood from my Rabbi's Kabbalistic teachings, that studying Torah and keeping Miztvos in this world does not change the soul, but only affects its merits and its sins do not affect the soul but the cleansing it gets. This also explains the reincarnation of the souls of seniors to kids.

For some comments to my question, I learned that some speculate that the soul might grow just like the body does, and the soul that comes down is a kind of a "baby-soul" that develops further into a "full-grown" soul.

What do our sources say about the soul's development over a lifetime?

  • I think this is a machlokess rishonim, when we say elokai neshama she'nasata bitehorah hi do we mean always and unconditionally, or do we mean that it was tehorah when we received it but what happens after that is up to us.
    – The GRAPKE
    Commented Oct 19, 2020 at 23:05
  • 1
    "studying Torah and keeping Miztvos in this world does not change the soul, but only affects its merits" - Surely the more mitzvos a soul accumulates, the greater heights it is able to reach in the olam haemes? In which case, whilst it may not change in essence, it still grows from the fact that it has reached new spiritual heights upon leaving the guf?
    – Dov
    Commented Oct 20, 2020 at 8:06
  • This is a fascinating understanding of how the neshama works. But if it's true, why bother learning mussar? Commented Oct 20, 2020 at 9:34
  • FYI at Kabbalah l'am there is an article by הרב ד"ר מיכאל לייטמן entitled התפתחות הנשמה. At Amazon there is a book titled “The Idea of Development of the Soul in Medieval Jewish Philosophy” Hardcover – 25 July 2007 by Philip D Bookstaber (Author) Commented Oct 20, 2020 at 11:05
  • You have to start with the difference between "soul" and "neshamah". The latter is sometimes used to refer to the soul, but sometimes to a specific aspect or function of the soul. The neshamah might be unchanging, but even if it is immutable, the ruach and/or nefesh could still be growing over our lifetimes. Commented Oct 20, 2020 at 18:19

1 Answer 1


In De Anima (On the Soul), Aristotle defined the soul as the life force "of the living body.” Aristotle explained that what made people “virtuous,” what distinguishes people from animals and fulfilled their telos was the development of the intellect.

Similarly, and like Aristotle, Maimonides wrote in his Guide for the Perplexed 1:1 that people should develop their intellect (from the Shlomo Pines translation, Guide, pages 21-23).

Maimonides writes:

משנה תורה הלכות דעות א:ד-ה

[ד-ה] כָּל אָדָם שֶׁדֵּעוֹתָיו כֻּלָּן דֵּעוֹת בֵּינוֹנִיּוֹת מְמֻצָּעוֹת, נִקְרָא ‘חָכָם’. וּמִי שְׁהוּא מְדַקְדֵּק עַל עַצְמוֹ בְּיוֹתֵר, וְיִתְרַחַק מִדֵּעָה בֵּינוֹנִית מְעַט, לְצַד זֶה אוֹ לְצַד זֶה, נִקְרָא ‘חָסִיד’. כֵּיצַד: מִי שֶׁיִּתְרַחַק מִגֹּבַהּ הַלֵּב, עַד הַקָּצֶה הָאַחֲרוֹן, וְיִהְיֶה שְׁפַל רוּחַ בְּיוֹתֵר, נִקְרָא ‘חָסִיד’; וְזוֹ הִיא ‘מִדַּת חֲסִידוּת’. וְאִם נִתְרַחַק עַד הָאֶמְצָע בִּלְבָד, וְיִהְיֶה עָנָו, נִקְרָא ‘חָכָם’; וְזוֹ הִיא ‘מִדַּת חָכְמָה’. וְעַל דֶּרֶךְ זוֹ, שְׁאָר כָּל הַדֵּעוֹת. וַחֲסִידִים הָרִאשׁוֹנִים הָיוּ מַטִּין דֵּעוֹת שֶׁלָּהֶן מִדֶּרֶךְ הָאֶמְצָעִית כְּנֶגֶד שְׁתֵּי הַקְּצָווֹת. יֵשׁ דֵּעָה שֶׁמַּטִּין אוֹתָהּ כְּנֶגֶד הַקָּצֶה הָאַחֲרוֹן, וְיֵשׁ דֵּעָה שֶׁמַּטִּין אוֹתָהּ כְּנֶגֶד הַקָּצֶה הָרִאשׁוֹן; וְזֶה הוּא ‘לִפְנִים מִשּׁוּרַת הַדִּין’. וּמְצֻוִּין אָנוּ לָלֶכֶת בִּדְרָכִים אֵלּוּ הַבֵּינוֹנִיִּים, וְהֶם הַדְּרָכִים הַטּוֹבִים וְהַיְּשָׁרִים, שֶׁנֶּאֱמָר (דברים כח:ט), ‘וְהָלַכְתָּ בִּדְרָכָיו’.

Thus, Maimonides understood the soul as "pure intellect," therefore, if one wants to use the term “soul,” they should refer to it as the intellect.

If we accept Maimonides' definition of the soul as "pure intellect," and if we agree with Maimonides that humans have a duty to develop that intellect, then it would seem that the soul develops.

  • I suspect you mix two things - development of a baby-soul (blank-slate) and sophistication of a grown-up one. Both thinkers didn't speak of the blank-slate but the latter. However the question was about developing from baby-state. Can you reflect on it, please.
    – Al Berko
    Commented Oct 23, 2020 at 7:30
  • @AlBerko “The L-rd G-d formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a nefesh chayah.” Thus, according to Genesis, Adam was created as an adult, pre-formed (grown-up soul). Or, if we accept the kabbalist secret that Adam was the first intelligent man with a soul, the neshama (baby-soul-blank-slate). Then we can agree with Nahmanides teaching that he had a mother and a father and that developed his skills for language early on (Genesis 1:27).
    – Turk Hill
    Commented Oct 23, 2020 at 14:27

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .