Pushing your enemy without using too much force is a Taiji principle.
Without learning pushing hands, you cannot say that you know Taiji very well. So pushing hands is very important in Taiji. Why?
Because Taiji concerns itself with the center using a centralized energy to make others lose their center .
When a person loses their center of gravity, although they may possess great physical power, they still cannot use it. So pushing hands is a basic Taiji technique used to make others lose their centre of gravity.
Of course, whatever you do must conform with the principles of Taiii and apply the principles of center.
An example of the principle of center.
1. When your enemy stands close to you and grasps your arm, let him come near; then slide your front leg with heel forward to his center. Because you are relaxed, your enemy’s force will be useless and his force empty.
At this opportunity you should push back, but not only with the hand!
You should push with your center (waist) and spiral the energy from the heel to the waist, transfer it to the hand and then move the weight to the front leg.
The energy will then become very strong.
By knowing the principle of pushing, you already have the key to open the Taiji door.