Reference for Makhshirin 6:1

הַמַּעֲלֶה פֵרוֹתָיו לַגַּג מִפְּנֵי הַכְּנִימָה, וְיָרַד עֲלֵיהֶם טַל, אֵינָם בְּכִי יֻתַּן. אִם נִתְכַּוֵּן לְכָךְ, הֲרֵי זֶה בְכִי יֻתַּן. הֶעֱלָן חֵרֵשׁ, שׁוֹטֶה וְקָטָן, אַף עַל פִּי שֶׁחִשַּׁב שֶׁיֵּרֵד עֲלֵיהֶן הַטַּל, אֵינָן בְּכִי יֻתַּן, שֶׁיֶּשׁ לָהֶן מַעֲשֶׂה וְאֵין לָהֶן מַחֲשָׁבָה:

[If] one takes his fruit up to the roof because of the worms, and dew falls on them that does not achieve <i>BeKhi Yutan</i>. If he intended that [to happen] it does achieve <i>BeKhi Yutan</i>. [If] a deaf-mute, [or] an imbecile, or a minor took them up they [the fruit] do not achieve <i>BeKhi Yutan</i> even if he hoped that dew would fall on them, because they can act but they have no intention.

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