Rotation is the result of linear movements
Rotation is the result of linear movements. There are no rotational moves in taijiquan.
This statement is rather difficult for beginners to understand. It will take some time (about 10 years) to gradually understand this.In general, energy itself is always linear. It is the interactions of different linear movements that cause rotational forces, ovals, and spirals to occur. Therefore, "straight line" is the original state of energy, circles (rotations) are results.
Source: https://practicalmethod.com/?p=36360