### Is there anything that is totally random?

• When I say totally random, I mean absolutely random, not pseudorandom.

If I want to say "totally random" numbers such as 1,26,17,4,1 and 27, although I see them to be totally random, they aren't. These are numbers that I think are influenced by my childhood, ideology and everything that I've seen.

So, what do you think? Is there anything completely random?

This questions seems to be a duplicate of Are humans capable of generating a random number?

could you please elaborate what you mean by universe? In my answer also, I stated that I don't really know how the universe is relevant to your question. Is there any chance you could expand on your question?

The answer simply depends on how you define "Random". In a very liberal sense, random is just something that is unpredictable. A fair coin toss, then, is sufficiently random. The problem comes in when you try to apply a more strict definition of random; perhaps an event is truly random when the probability of the possible outcomes is equal. **But in a deterministic universe** (and much of what we see in our universe very much appears deterministic, even if it isn't "underneath"), **there is only ever one possible outcome to an event.** So randomness defined in this way doesn't even make sense.

Nothing in Nature is random. A thing appears random only through the incompleteness of our knowledge (Spinoza).

@stoicfury I'm just wondering here... Why haven't you added your "The answer" comment as an answer? It perfectly sums up everything I'd think to put in an answer and I bet at least 5 other people would already agree.

@Cawas - I had thought my response deserved only comment status at the time and hoped someone would post a more thorough response. Rex's answer is the best empirical answer IMO. I will add mine only because it seems no one really touched on the the determinism / randomness conflict, although ThisIsNotAnId's answer briefly touches upon it.

Read theory of classical chaos (are you reading?). Off course there is. And a lot and for everybody. Everyday is pretty random. You just THINK you understood it, right? No.

@robingirard Wouldn't Spinoza, being a monist, think potentiality (that undetermined part of material beings) was imperfect actuality?

Are you asking about "ontological randomness" or "mathematical probability theory's randomness" or both?

I had a professor for Analytical Chemistry stipulate that at the molecular level, no occurrence is completely random, using a constructivist model, I would argue that if nothing is random at the smallest level, nothing can be random at the level of naked observation.

• To answer your question, or at least get at some sort of picture, let's consider the following. What is random? Hmmm. Without getting into the details of the matter, or philosophical implications, we may define "random" in a very intuitive manner as this will mostly do for a discussion of this scope. Let us then propose that an event which is "completely" random is one for which it is logically (or formally, i.e. in the sense of mathematical rigor) impossible to associate any rule, pattern, or reason. This is, of course, where it all gets tricky.

In the way "random" has now been defined, it may be possible to generate an event, at least cognitively, which would be viewable as truly random. To take your example a bit furhter, let us conduct a thought experiment. Imagine we're walking down a busy city street. We decide to ask every person that passes by, and decides to stop and give us five seconds of their time, to pick a number. By this, we may construct two sets. Let set X denote the numbers we record, in the order we encountered them; and let Y denote the set of indicies of the people who stopped and gave us a number. So, for example, if the third, seventh, and twelfth person we asked stopped and gave us a number, Y = {3, 7, 12}. Certainly, the sets X and Y may not be random in the sense that we have defined.

But, then we may ask the question why the sets have the particular pattern or rule associated with it. Could there not have been different sets? And so, by our criterion for true randomness, the reason the sets X and Y are what they are, is random. I can't come up with the proof for the criterion off-hand, but I suspect Goedl's theorem's in there somewhere.

It is worth noting that by our definition, it may be the case that no event which occurs in nature could be viewed as random. So, that may answer your question about there being anything truly random in the universe. On the other hand, we may very easily have events that qualify as truly random as long as they exist in some "virtual" reality as the one discussed in the example above. But, it's truly an understatement when I say that that's a topic to be discussed another time.