"If you know not, then you can say not that it's linear." - this is a classic appeal to ignorance.
An appeal to ignorance is commonly used to defend unfalsifiable claims (like bigfootspacealiens).
Here's the problem.
There are only two possible options.
(1) your thoughts (and actions) are contextual (caused by previous experiences, including your biology).
(2) your thoughts (and actions) are random (uncaused by any previous experiences).
If you pick #1, then your thoughts (and actions) relate to your memory and the world around you (contextual). This means your thoughts (and actions) are potentially USEFUL TO YOU AND OR OTHERS.
If you pick #2, then your thoughts (and actions) don't necessarily relate to anything at all. And as a matter of fact, statistically, it would be extremely unlikely that any RANDOM thought or action would be even remotely or incidentally USEFUL TO YOU AND OR OTHERS.
Now you might try to mix the two options, some caused, some uncaused, and that's fine.
Your useful thoughts and actions MUST BE CAUSED.
YOur "free" thoughts and actions are TAUTOLOGICALLY COUNTERPRODUCTIVE (99.999% of the time).