Again, why not just "Lui non piacciono i gatti". what's the point of the "A" at the beginning?
In Italian "piacere" originates from what in English is the object:
Subject: i gatti (cats)
Verb: non piacciono (aren't liked)
Indirect object: a lui (by him)
And that's how it comes to be; the sentence could also be written in the order I listed them, and also as "I gatti non gli piacciono".
Nope, 'gli' is 'a lui': the full list in the usual order from I to they is mi, ti, gli/le, ci, vi, gli.
The pronoun particle 'si' is special and it has three main uses:
Reflexive: it substitutes both forms of 'gli' when the object is the same as the subject, e.g. "lui si lava" (he washes himself), "loro si amano" (they love each other), "lei si è comprata un vestito" (she bought herself a dress)
Impersonal: it makes the subject generic, e.g. "si dice" (people say), "si mangia bene" (one eats well, i.e. the food is good), "si usa" (people use or are used to, i.e. it's custom).
Passive: similar to the previous, it makes the subject the object of the action, e.g. "si vendono biglietti" (tickets are on sale)
In this case, if you were to say "I gatti non si piacciono" it would mean "cats don't like each other"; to generalize you'd have to remove the pronoun entirely: "I gatti non piacciono" (cats aren't liked).
Isn't piacciano plurar for "Loro" ? I dont get it. Is the piacciano here because it refers to the "Gatti" not to "Lui"? Am I correct ?
"By him" makes the translation make sense, but unfortunately the hover over "A" only gives the options "to", "for", and "at" as translations.
It's not literal. piacere actually means is pleasing to yet most of the time Italians flip the word order so the thing doing the pleasing is at the back.
Isn't "The cats are not liked by him" just as valid? Or does the sentence structure matter more here?
What about if I were the one who didn't like the cats? Would it be "A io non piacciono i gatti"?
"A me non piacciono i gatti"; "io" like "I" can only be used as a subject. Or you could say "Non mi piacciono i gatti".