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Try to keep this post civil
I am interested in having a discussion about this, so feel free to debate over this
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Free will is required for God to exist, without it God does not exist.
Without free will there is no good or bad, only good and bad actions. Just like how we don't consider a hurricane killing people as bad, we just consider it a bad action since its just obeying what physics tells it to do. If human beings are no different to hurricanes then how can a murderer be considered evil, or anyone or anything for that matter, if all they are doing is obeying their genetics and nurture.
Free will does not exist if every event can be perfectly predicted.
Back to the hurricane, we don't believe it has free will, since it just obeys the laws of physics, if you had the correct amount of information and the require models, you could perfectly predict its behaviour, where it will be at all times, how big it will be ect... Now this might not be practical or even possible, but if in principle it is possible to predict it perfectly then it does not have free will.
If human behaviour can be perfectly predicted, that would mean if you knew everything about a person every neuron, every molecule, every atom. If you knew all this information you would know exactly what neurons would fire, what muscles would move and what would happen after every event.
What about randomness, not everything can be explained by science?
Random is a lie. When you flip a coin we say it is 50/50, but in reality if you knew how exactly you flipped the coin with what force, the weight of the coin, the air molecules you would know what it would be, it would not be a 50/50 it would be a 100/0.
When computers create 'random' it is only pseudo random, when we use random it is because we lack a better model and the sufficient information to make a better prediction.