Bored with my partner

Why should he change to be someone who he is not?

I am not trying to be mean, but if you truly loved your boyfriend then you wouldn't list all of his qualities and say how wonderful he is, and then, in the very next breath; say how much he bores you and how uneducated he is.

Love means accepting your partner for who they are, faults and all. If you cannot do that, then you need to move on.

Let's break down your assessment of your boyfriend, shall we?

"He is a lovely person, very caring and understanding. I am very proud when I see how he behaves in front of other people and how polite he is."

Is he your boyfriend? Or your child? While we all want someone who won't embarass us in front of our friends, this comment makes you sound more like a parent (or a saleswoman), than a loving girlfriend.

 "... he does not fulfill me intellectually... He is however too serious, he is not fun, he doesn't plan things to go out and even if we do go out I am not excited about it."

You can take him out to show off his manners, but you won't have a good time?

"I have always enjoyed deep conversations and I am very curious about everything in life. I love to discuss things but my boyfriend he is too quiet and sometimes only reply with one word. It is not interesting for me. He doesn't read or educate himself."

Are you with him because you love him? Or because you would enjoy a good lecture series?  If you want intellectual stimulation, take college classes.

"I would like to ask ... whether I could somehow motivate him to change? I wouldn't want to leave him because he is a wonderful person. However, I find myself starting to be impatient and bored with him and than I nag him..."

Why do you insist that you think he is such a wonderful person, yet denigrate his entire being? If he's so wonderful, why should he change?

Please stop trying to fool yourself. End this relationship and give this man (and yourself) a chance to find happiness with a mate who appreciates him for who and what he is.

It's the right thing to do.

It is clear that you feel this dear man is "beneath you" intellectually, and that will never change because: (1) He IS WHO HE IS!  and (2) You ARE who you are!  Why don't you just accept him for the wonderful man he is, with a good heart, good common sense, kind, loving and well mannered?  Oh, is that NOT ENOUGH?

Then move on. Stop being selfish and let him go. YOU will always be a Nag because you allow yourself to feel "superior intellectually" and you look down on him, thus you really don't have proper respect for him as a person and that is not likely to change unless you seek therapy with a licensed Psychologist who can help you realize why you expect so much of him and expect him to change to somehow meet your requirements.  You could make the decision to (1) Love and accept him for who and what he is, appreciating all his good qualities; (2) DON'T EXPECT HIM TO MEET ALL YOUR NEEDS; and (3) Seek intellectual stimulation outside the relationship by joining a Debate Group, Political group, or other. Cultivate a group of friends who enjoy intellectual debates and meet weekly, bi-weekly, or whenever. 

If you cannot be happy after doing this, then you know HE is NOT THE MAN FOR YOU.  Having experienced the same thing in several long-term relationships when I was in my 30's, I broke up with "wonderful" men.  However, 30+ years later, I still have not found the PERFECT MAN, and am alone.  We all have both assets and shortcomings.  Learn to appreciate the good in him, accept that which is lacking, and LOVE HIM for the person he is.  Maybe there are things about YOU he would like to change, but he doesn't pick fights with you to try to get you to change. He is too nice to do that.  It is not nice of you to pick on him about the few short-comings he may have.  Maybe you're the one who is not much fun!  Maybe he's on pins and needles thinking you are going to "find fault" with him when you go out.

It's a 2-way street.  Good luck.