Where does a reason or belief reside? Does a reason have arms and legs of its own, such that it can actually cause anything by itself? Can any belief have any effect at all without first becoming an essential part of who someone is?
A person must first adopt a belief before it has any power to cause any effect in the real world. And we adopt a belief, as our own, only if it serves some practical purpose.
The purpose, like the reason, exists only within the person. Within the universe, biological organisms are the only thing that come with a built-in purpose. And among the biological organisms, we humans have evolved the most advanced ability to think and reason.
Beliefs and purposes are never external causes that coerce us to act against our will, but rather they are an essential part of us that help us formulate our will in practical situations requiring deliberate thought.
Our reasons are causative, but the cause remains us. It is still us acting freely upon our own purpose and for our own reasons.
If you believe that one must be free of causation in order to be free, then freedom is impossible. Freedom from causation is an imaginary freedom that cannot possibly exist. Without reliable cause and effect we can never reliably cause any effect. So we really need a deterministic universe.
Because freedom from causation is impossible, no one actually means “free from causation” when they use the word “free”.
When we use the word “free” we imply freedom from a specific constraint. We set the prisoner free from jail and set the bird free from its cage. The Pilgrims and other separatists sought freedom from being required to attend the church of England.
The child seeks freedom to decide for himself, of his own free will, whether to wear a coat before going outside. And the driver who was hijacked by one of the Boston Marathon bombers, and forced at gun point to assist in the escape, wanted to be free from that coercion.
In none of these cases, including those involving free will, was there any presumption of being free from causation.
If you choose to define a concept in terms which are impossible to satisfy, you destroy the concept. So don’t do that.
We need ordinary free will to make that very significant and meaningful distinction between acting autonomously rather than under the control of others. It is a big deal.