They're very dangerous and should always be used with caution.
Wow. "Dangerous" and "caution." How about dictionaries can be misleading and should be used wisely? A dictionary is a very useful tool (how would you ever hope to learn new vocabulary?), but like any tool, it comes with a set of instructions. Of course, I completely agree that reverse checking and checking in context are required. You can't just open the dictionary and choose a word out of the list because it looks nice to you. That's something I always told my students. Nevetheless, what greater learning opportunity than
diving into the dictionary for fancy words
1) you correct the student and explain why this particular word doesn't fit the context, and
2) you show the student how to use the new "fancy" word.
The student learns two things at once. Huge win :-)
It's exactly what small children do when learning their mother tongue, BTW. They hear a "cool" new word and try to fit it into any conversation ;-) With time, they learn when the usage is appropriate.
A good dictionary is a blessing, a bad dictionary (see: Stanisławski) is a terrrible thing, but I cannot imagine either learning a language or translating from one language into another without a set of them.
I've heard the Polish used when I wouldn't use the English
Any examples please?
Back to the OP, since I'm not sure if he's a native speaker I can't be sure on what kind of difference he has in mind between wise and intelligent let alone how to render the distinction in Polish.
That's radical. I might be making a huge assumption here, but to me, the OP was asking about a simple distinction between "someone who has the innate ability to learn (acquire new skills or create them) and adjust their behaviour to changes in the environment" (intelligent) as opposed to "someone who has lived a long time and / or has had a lot of different experiences and has the ability to teach others based on, and / or behave accordingly to this experience" (wise).