Often during my training, I find myself being caught up in the finer details of getting a technique right. At this time my sensei, whoever it may be (aikido or TSYR) will often mention a certain prinicple of the art that will correct the technique I'm struggling with. It is easy to forget that the techniques are merely a tool or medium through which to teach a principle. This has become clearer and clearer to me as I practise both arts. Principles are the underlying concepts that make an art what it is. The techniques are what we see, externally. Bend the arm this way, place your feet like this. The body moves a finite number of ways, many techniques are similar across different martial arts. However, the principle guides technique and the difference lies in how the technique feels when it is applied. Someone who is a good technician can get the same result on the surface but at a deeper level it feels hollow. Principles are applied to many techniques and a practitioner who grasps a principle will have stronger technique. Now, I often try to see the principle behind the technique that I am learning.
What is really intriguing is how many principles overlap in the two arts I study. Such things as moving from the centre, pushing (never pulling), upright posture and of course, timing and placement of one's body in relation to the opponent.