By the time fourth or fifth grade hit I had some idea about statistics. I used to answer a friend’s questions, “Do you think you will take a trip in June?” with responses like. “80% yes.” I was a Determinist. Determinism is the belief that all events are caused by prior events including those classified as “free will”. We got the way we are by previous events and out experience and physicality determines how we will act. I am still one, but it has become less important in my life.
One of the more pressing mental issues in my life is some good dose of some form of ADHD. Likely I will need to bring this up later, separately, but it does have an impact on motivation. Even by fourth or fifth grade consciousness of these issues was at least in part there. I had a hard time getting going on things, even fun things.  Being a determinist I thought maybe I was preordained to have no motivation. There seemed no reason to do anything. I decided that I better test it. I sat down. I did nothing. I really cannot say how long this lasted. Buddhist say that the Buddha meditated for 49 days. I likely did not last 49 minutes. I did last more than 49 seconds.
In sitting contemplating not having any motivation I came to some conclusions.
1. I was bored just sitting.
2. Sitting was not being fun.
3. Maybe I was preordained to have motivation to do something.
4. Maybe my current state wanted fun.
I was not preordained to have motivation to only sit.
It did not take long but I decided that true or not, determinism was not very much fun. I did find that the attitude was not easy to explain to others my age. I got up. 

I have heard many arguments against determinism. None really hold water for me. Simply stated most of these arguments are that because you cannot observe a state without changing it you cannot know what the condition is  that will bring about the next position. Just because you cannot know it, does not mean it does not exist. Because you cannot determine what will be does not necessarily mean that it is not predetermined by the previous state.

Perhaps it will come up again, but these thoughts led me to think about models and scientific theories,,, how they are approximations always. I have generalized this with the following statement.
“The only adequate model for how anything works is the entire totality.”