Indeterminism is the theory which is often referred to as the anti-determinism (read my article on what Determinism is here). It is the belief that there is no causal relationship between events so actions just sporadically occur; there is no genuine free will nor is there determinism as we are simply living in a world of random events. Not all events are causally necessitated by events in the past as the same past can lead to different future states. Indeterminism weakens the link between the past and the future and gives way for free will as the world is not a determined place. Our decisions are ultimately dependent on indeterministic physical processes so we have random and unpredictable acts. This idea is supported by recent advancements in physics as when scientists studied the movement of electrons, they noticed an unpredictable trend which indicated that we may not be living in a determined world. Electrons in a magnetic field are in superposition (they can either spin-up or spin-down from their current state) but it is impossible to predict their actions as the electrons do not have determined events: they can change the event even if the cause is in the present. This notion of electrons not living in a determined world has been adapted by philosophers and applied to our brains: when we make decisions, not all of our decisions are not causally determined by prior events so our actions are often sporadic so we cannot be held accountable for said actions.
Indeterminist thinking may be backed up by science but, to put it bluntly, it is most probably not the best theory to consider in the question of Free Will and Determinism. If Indeterminism were to be true, our actions would be sporadic. This means that we would not have control over our actions because they are random and unpredictable. This would also mean that we cannot be held accountable for our actions as there is no causal relationship between events: things just happen so we are not genuinely free as we are not held morally responsible nor are we able to control our actions. How can we be free if we cannot control our actions? To be genuinely free, we must have control over our actions. The only way we can perform responsible actions is by acting on good reasons. Indeterminism cannot explain how our actions and decisions can ever be under our control because it renders actions/decisions random events. Imagine how impractical life would be if everything we did was random and uncaused! Here’s a thought experiment: John and Lucy are considering marriage. Whilst John is ready to tie the knot, Lucy is not too sure of what she should do. Lucy decides that she will flip a coin every day and if it lands heads-up four times in a row, she will marry John. Eventually, the coin lands heads-up four days in a row and Lucy marries John but was this decision free? Lucy did not have any control over whether she would marry John, the decision came down to the random probability of a coin landing heads up four days straight – it almost seems as though the decision wasn’t hers. This thought experiment simply exemplifies the issues with Indeterminism: we cannot live responsibly if everything we do is random.