Historical records have shown that the arts of Xingyiquan and Taijiquan were inspired by spear methods. The concept is to insert your spear tip into an opening and take the line with your superior alignments. This action is both attacking while diverting and often turning the opponent. Most infantry men would be likely to swing their weapon incorrectly in the heat of battle. The opponents wrists will cross your centerline before their weapon. This allows you to insert the tip and divert upward. A Facing Up Palm or a Spiraling Up Palm are very good for this effect. This generally causes the person to stiffen up in an attempt to power through however when you divert them from the wrist , a small lift at the wrist equals a bigger lift on the weapon. The movement does not have to be very big to cause the weapon to be diverted over your head. All of this is powered through from the natural JIN generated from the stepping method . The entering palm must be turned by the turning of the waist so that the musculature can stay soft and the joints open. If you attempt this with a stiff arm you will always fail. You have to have faith in the softness for it to be effective.