Hi GDA,
There is “cause and effect” of the material world and there is “cause and effect” of the mind.
When we cling emotionally or mentally to anything we create a consequence that binds us to the world of illusion. This is “cause and effect” of the mind. The act of clinging “causes” the “effect” of karma. Karma, within this context, is a mental bondage to the world system, which is slavery to illusion.
Think of an actor in a movie who does not remember it is pretend. He thinks the events are real even though they are just pretend. Let us say in the movie this actor’s movie daughter dies in a horrible accident. Since he has forgotten it is all just pretend, he will react as if his “real” daughter has “truly” died. He is bound by the illusion due to his act of mental clinging. Since he believes it is real, it creates a karmic consequence. It is real for him and he suffers the consequences of his clinging to it as reality; this IS the creation of karma. His clinging to a false reality created emotional consequences that would not occur if he had recognized it was all just pretend! When we cling to the illusion of life we suffer the consequences that come from that clinging, those consequences are karma. No clinging, no consequences, no karma!
On the material plane there is also cause and effect, if I hit may hand with a hammer, it will hurt. If I commit a crime and get caught, I will suffer the consequences of the law, even it the laws are arbitrary and inherently illusive. This is karma of a difference sort and is not inherently related to karma caused by clinging. If there is no clinging, we do not accrue karma of this sort, while we are still subject to the physical and social “cause and effect” consequences of the material world system, which can be referred to as karma, but it is of a different sort.
To be mindful of our thoughts is a tool that may be used to transcend their control over us. The only control our thoughts have is the control we give them by clinging to them. It is believed that once we are aware/mindful of our thoughts we will recognize their inherent illusory nature and therefore, the futility of clinging to them.
Clinging, then, becomes a volitional act, once it is volitional we are free to choose not to cling. For most of us, clinging occurs automatically; it occurs as a consequence of conditioning and becomes an habitual act, that is, we have no conscious choice over it. By being mindful of our thoughts, we are able to make the conscious choice not to cling; with conscious choice clinging is no longer an habitual compulsion over which we have no control.