It may sound counter-intuitive but I believe it's neither free will nor pre-determined fate.
In fact, I would suggest that both free will and pre-determined fate are purely concepts created by the human mind.
A rough analogy would be us looking at the colors of a rainbow.
When we look at a rainbow, the cells in our eyes are excited by different wavelengths of light, and they then generate nervous impulses.
When our brains receive these signals, they produce an internal representation of the light that we can visualise.
These colors thus exist only in our minds, not in reality. In fact, whatever we see exists solely in our minds through an internal reality made up of mind-objects such as the rainbow and its colors.
This extends to our senses of hearing, smell, taste and touch.
This internal reality is at best a flawed and incomplete simulation of ultimate reality.
Going back to the concepts of free will and pre-determined fate; in much the same way, these are the mind-objects that we have fabricated to try to make sense of causality in ultimate reality.
Just as the rainbow and colors in our internal reality fall short of depicting ultimate reality accurately, so both the concepts of free will and pre-determined fate do not paint a valid or complete picture of causality that is rooted in ultimate reality.
