It's 5 months since I lost my dad in a factory accident. His manner of death is obviously the biggest tragedy of my life, but now when I contemplate about it, the Physics of the event seem so unlikely. A projectile (hinge) ejected from a machine in his direction, and if my dad (who was just passing by) weren't in the extremely precise space and time, he would have been alive today. The likelihood of this event feels negligibly small, and yet it happened.

This prompts me to think: do theoretically improbable events occur due to inherently deterministic nature of universe?

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    Theoretically improbable events would occur regardless of whether the universe is deterministic or not. The only difference is in interpreting probability. In the indeterministic interpretation the randomness is inherent in nature, in the deterministic one it only reflects our lack of knowledge about full set of conditions that determine the events. Mathematics works out the same either way.
    – Conifold
    Jul 4, 2019 at 3:31
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    I am sorry for your loss. I do not think the universe is inherently deterministic, nor do I think it is random. That means there is more going on than we realize. Best wishes. Jul 4, 2019 at 4:40
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    Short and lovely comment @frankhubeny. Would +1 it multiple times if I could.
    – Rushi
    Jul 4, 2019 at 4:48
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    Free will would be an example of something non-deterministic and non-random. So there are more possibilities than determinism and randomness. Jul 5, 2019 at 1:18
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    Determinism is also debatable given quantum mechanics. Randomness is put in to avoid dealing with agents at all levels making free choices within constraints and in the process of acting within constraints creating predicable patterns. That would be another model, call it an organic model, different from the computer model. Reality may be different than either of these. Jul 5, 2019 at 12:10

1 Answer 1


Jimit, let me say first you have my condolences. Here I will provide another way to look at unlikely tragedies.

In my previous career I had to deal with finding the root causes of catastrophes in our factories. Fortunately, none of these involved loss of life, but they had huge consequences for our business. What I discovered was that these disasters were not caused by what we called single-point failures. Instead, there was a causal chain of events which led inevitably to the catastrophe and if any one link in this chain were missing, the accident would not have occurred.

For a simple example, we would take receipt of incoming chemicals which would occasionally contain impurities which would cause our processes to crash. I would ask the question, why wasn't the incoming material tested for the presence of the impurity? Because there was no specification of the need to test for it in the incoming inspection process, or the material wasn't subjected to incoming inspection, or the inspection machinery was improperly calibrated, etc. Had any of these measures been taken in advance, the crash would never have happened.

(By the way, the concept of a causal chain is regularly used to determine the sequence of events leading up to the crash of an airplane- which almost never occurs via a single-point failure.)

So, even in the context of an apparently random and unpredictable tragedy, there will usually be a time sequence of events preceding it which are at least partly deterministic, and hence the accident wasn't really random or unpredictable: the outcome of the causal chain was in fact predictable i.e., a deterministic outcome.

I cannot guess without more data the reason why that machine ejected a hinge with deadly force, but let us speculate it was due to the failure of a part inside the machine. Parts are not supposed to fail, so why did that one? Perhaps it contained a flaw. Parts are not supposed to be flawed, so why was that one? Perhaps the flaw was hidden. Hidden flaws must be looked for, why wasn't this one found? Perhaps the part escaped inspection. All parts must be inspected, why wasn't this one? Perhaps the inspector was interrupted during the task. Inspectors are not supposed to be interrupted, why was he? Perhaps his supervisor had an additional task for him that day- and so on. Each link in the causal chain was not a random event, so the accident was not a random event- it was inevitable, when seen in this way. And the outcome was avoidable, had there been measures in place to break the chain.

And the last link in the causal chain: Why was your father passing by the machine at the moment it failed and shot out a hinge? Now we enter the realm of probabilities and statistics, but I will stop here.

Again, I am sorry for your loss.

  • thank you for your condolences. The explanation you gave is fabulous. Jul 5, 2019 at 16:15

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