Sin (or any crime) is not defined by the victim’s response to it. Is it?
Some are, but I get your drift. Lets use a different example then. You are happily motoring down the highway, cruising at 65. When the speed limit drops to 55, you arent looking and dont see it. Have you broken the law? Yes. Is that disobedience to the law of the state? Yes. Intentional or not you disobeyed a lawful command to limit your speed to 55.
Sin is defined, as the Church teaches, by object, intent, and circumstances.
Citation? I read that in 1750 regarding Morality of Actions which you told me below was not equal to sin… you are confusing me (and that is easy today)
And ANY of those three being sinful makes the entire action sinful. If the object is evil, the whole thing is sinful even if your intention is perfectly good. If the circumstances are evil, the whole thing is sinful even if your intentions are perfectly good.
So, again, your example is simply an innocent mistake. Not a sin. As you note “if” the briefcase contained a million dollars. The person mistakenly taking the wrong briefcase did not know such. There was no intent to steal a million dollars (or to steal anything).
The question was not “Sin”, but crime. Was it a crime?
It’s not logical to think that someone taking a wrong briefcase, by mistake, does so imagining there is a million dollars in it.
The point was that intent was irrelevant. I can only hope that you would be so magnanimous should you be the one to lose something in these situations.
Of course not.
The CCC 1750 cites Catholic teaching on the sources for morality.
Acts that go against those criteria are, likely, occasions of sin (whether mortal or venial).
And we know that venial sin does not require full knowledge or intent.
What is the source for the citations you provided? A dictionary, or Catholic teaching?
I have already addressed this.
I disagree it is possible to sin without intent.
Fair enough. Disagree away
It is certainly possible to do wrong, or intrinsically evil acts, without intent. As the Catechism notes, sin involves “disobedience.” That involves intent, necessarily (though you may think otherwise?).
So it is possible to do evil without sin? Very interesting.
If you think people can sin without intent, please show where in the Catechism or other Catholic teaching this is clarified. Thanks.
Already done. I have asked you three or four times to provide source material for your views and you have failed to do so. I will not reply any longer without at least a modicum of proof on your part that your views have some basis in Catholic theology. I will allow you the one 1750 MAY apply, if you squint a bit at the text

, but you have provided nothing else.
FTR, I am quoting what the Jews viewed as sins since they are our forefathers and out of them came salvation to the world.
In the post-exilic period the inclination toward idolatry was eradicated, and the disposition toward fornication was weakened (Yoma 69b). The list of sins in the confession of Yom Kippur gives an idea of the rabbinical conception of sin. The “'Al Ḥeṭ” was extended from the simple formula in the Talmud (Yoma 87b) to that of the Geonim, which includes the Ashamnu, 'Al Ḥeṭ, and “'Al Ḥaṭa’im” (“Seder R.'Amram,” p. 48a; see also Aḥai Gaon, “She’eltot,” § 167). The “Ashamnu” is in alphabetical order and enumerates the following sins: “trespass, treachery, slander, presumptuousness, violence, lying, scoffing, rebellion, blasphemy, oppression, extreme wickedness, corruption.” The “'Al Ḥeṭ” qualifies man’s sins and makes him ask forgiveness for the sins which have been committed against God “either (1) by compulsion or (2) voluntarily, (3) unwittingly or (4) with knowledge, (5) in private or (6) in public, (7) presumptuously or (8) without intent.” The “'Al Ḥaṭa’im” classifies sins as those “for which we were obliged to bring a trespass-offering, . . . a burnt offering, . . . a sin-offering; for the sins for which we were obliged to suffer the penalty of receiving stripes, becoming childless, being extirpated or killed by death from heaven, four modes of death by bet din” (“Seder R. 'Amram,” l.c.). The single alphabetical list of the “'Al Ḥeṭ” was formulated later; it is mentioned by Maimonides, and is found almost entire in the present “Minhag Sefarad.” The double alphabetical list of the “'Al Ḥeṭ,” as found in the “Minhag Ashkenaz,” dates probably from the thirteenth century (comp. the Vitry Maḥzor, pp. 390-391, and the prayer-book and Maḥzor for the Day of Atonement).
SOURCE