They are attracted to each other by their passion, their original thinking, their idealism, their search for authenticity and their romanticism. They appreciate each other's sensitivity, emotional depth, creativity and uniqueness. Both are dreamers and spend a lot of time imagining their future and telling each other their dreams. They are both very introspective, understand their deep mutual feelings with empathy, and they listen to each other, and support each other.
The main difficulty is the emotional instability that can occupy both partners. And if it happens at the same time, there will not be one to help the other, and the relationship can become very cold. 4s are very attracted by what they miss, they understand and love each other when they are in their dreams, but may have a hard time accepting themselves as they are when they face reality.