I'm wondering the existence of probabilities in general, either in maths ou other.

①➡ I have three balls(1, 2 and 3) inside a bag, and I close the bag. I mix the balls and I take one out. How do I know which one I grab before I pull it out? I had those kind of problems in highschool when I was studying math. I only resolve them with probabilities and some known facts.

②➡ Now imagine a real life situation where I'm walking through a street and I turn a corner. How do I know if there's someone in the other side of the corner that I can run into? If I can't see the other side of the corner I don't know if it's approching someone. Unless there's mirrors or something... But can I calculate a probability? Of course I can know how many people walks through that street at that time and I know that in some days is more crowded than others, and hours too.

③➡ Now in physics, there's is a theory called "Schrodinger's box", wich exposes a problem such as: I put a cat in a box and close it. How do I know if the cat is dead or alive? I know that there's only two solutions: or it dies or it lives.

So in case one, I'm bloqued by what I can't see. If I can't see which ball I'm taking out I don't know which comes out. So the main problem is me in a way, 'cuz I'm incapable of knowing for certainty which comes out. Look, it's not that reality doesn't know the answer it's that I don't know(point). Reality is not a person. The curious one is me. But I'm incapable of knowing what really happens at all the moments since the problems beggins, so I'm a searcher for the certain result. PS.: if I wrote a program to determine wich ball the user would take I could know the answer to my problem with certainty.

In case two, even if I made a research I could still not know the certain result. But If a helicopter was filming the place he knows what's gonna happen. He knows if I encounter a person or not. He's seeing it! But now imagine if he wanted to know if me and that person run to each other. That is a thing of the moment it happens too fast, one of the persons can desviate.

In the third case, it's like the balls. I can only know if the cat dies or lives if I open the box and see it with my eyes. So again, the certain solution to my problem is me. Because the answer is known and certain for reality. I'm the ignorant one. It's not that the problem isn't solvable or hasn't an exact solution. Is that I don't know enough to determin a certain solution.

Conclusion: what I'm trying to say supported by this arguments is that one confronting a problem that seems unsolvable tries to estimate the solution, although is not the exact one. And appears to be only a misinterpretation of reality, since we don't know all the facts. You can't write a successful algorithm without knowing every steps. So to use probabilities to solve a problem doesn't exactly solve a problem. Assuming that all problems not made by man have reasons and solutions, all problems have the right facts and the right algorithms, therefore to solve a problem we need reasons, facts and solutions, things that probability can't do to solve a problem. That's based on humans ignorance, since probability was created by humans and is not a perfect system, so it's also based on ignorance. Since ignorance is also lack of reality, probability is not real.

Well, we all know that mathmatics is exact. The only thing that's not exact it's probabilities.

Are probabilities real? Do they represent any objective quantities or are they just subjective to the person calculating them.

PS.: It was invented by humans but don't fall in the graces of humans criativity.

• Welcome to Philosophy SE. Interesting topic. However, questions of the form "Here's my opinion, what do you think?" are not encouraged. Please be a little more specific in the questions you are asking. – Alexander S King Nov 4 '15 at 21:31
• Didn't get it. Should I ask more scientific questions? I assumed I could discuss philosophic topics, for so I asked the opinion of others. Please enlighten me about what I should or not post and what is this stack about. Thank you and sorry for the confusions. – Inês Barata Feio Borges Nov 4 '15 at 21:41
• You are correct, this is about philosophical questions. However the questions need to be specific, so that other users can provide objective answers. In your case you might want to ask "Are probabilities objective?" or "How do probabilities provide useful factual knowledge?" – Alexander S King Nov 4 '15 at 21:53
• Of course probabilities are not exact. Probability is not some kind of a trick to limit chance. Chance is always there. Probabilities are only a tool to know your chances but reality may have a different idea. About Schrodinger box don't spend your thought. To your tutor say that you agree with him. – John Am Nov 4 '15 at 21:55
• Chances are always there for you. Atoms don't guess whom they are joining. The just join. Dogs don't think about probabilities. That makes them more or less ignorants? – Inês Barata Feio Borges Nov 4 '15 at 22:03

You can't write a successful algorithm witout knowing every steps. So to use probabilities to solve a problem doesn't exactly solve a problem.

This isn't true: there are several algorithms which use probabilities and randomness but achieve exact final results. See Monte Carlo methods and Las Vegas algorithms. Randomized algorithms have many applications. One example is Quicksort. More generally, optimization and search problems benefit from randomization and probabilistic approaches, since they are computationally hard, and the only deterministic algorithms to solve them are brute force searches which have to go through the whole solution space to find the answer.

Most programming languages, Python, R, C++, etc... included random number generators, which can be used to insert randomness into and algorithm.

In the third case, it's like the balls. I can only know if the cat dies or lives if I open the box and see it with my eyes. So again, the certain solution to my problem is me. Because the answer is known and certain for reality.

This is also incorrect: In the case of quantum mechanical experiments, like the schrodinger cat you just mentioned, the uncertainty in inherent to the system, it is not due to the ignorance of the operator. Not only is the uncertainty inherent to the system, the probabilities in question are objective because they are determined by the quantum wave function of the system.

Per Quantum Mechanics and Heisenberg's uncertainty principle, Nature is not "precise and exact" (i.e. it is not deterministic). At the lowest level, phenomena are inherently probabilistic and uncertain, although the role of the observer and the general implications for epistemology are still a matter of debate.

Einstein famously disagreed with Quantum Mechanic's randomness, saying "God does not play dice", and spent the second half of his career trying to falsify Quantum Mechanics. He failed, as shown by theoretical results and experimental evidence in the 80s and forward.

Is probabilities real?

More generally there are two interpretations of probability, Bayesian and frequentist. In the frequentist interpretation, probabilities are "real" in the sense that thy correspond to frequencies that the event they describe might or might not occur.

• Comments are not for extended discussion; this conversation has been moved to chat. – virmaior Nov 6 '15 at 9:28
• I've moved the comments to chat... @AlexanderSKing thanks for being proactive on the editing front. – virmaior Nov 6 '15 at 9:29