“Reality” and “existence” can refer to one of the following two things:
- model of reality (or formula for calculating predictions)
- category that includes certain predictions (those we accept) and excludes others (those we reject)
If you come to think about it, the two aren’t very different. Formulas can be used to derive predictions that we accept in order to generate the category we call “reality”. So #2 can be derived from #1. Moreover, formulas cannot always be reduced to a category (e.g. if they don’t have a limit on the number of predictions they can generate which is pretty much always the case) but every category can be represented using a formula. Hence why I side with #1 – formulas.
So that’s what reality is: formulas.
But this conclusion has the property of making some people afraid of it because it appears to them that it signals the beginning of solipsism. Which is stupid.
The reason we think there is such a thing as reality independent from our minds (even though there isn’t) is simply because our models of reality change through time. And they do so in a non-random and progressive way. One has only to look at how these models are created. Basically, we have some quantity of observations. Each observation is basically an event that has certain similarities to other observations/events and certain differences. Based on these relations we can construct a model that represents these observation in a way that no other possible model does. As time goes on, we acquire new observations. So our set of observations increases over time, and if we were to follow the steps of creating a model of reality in order to reflect this change, we would quite likely end up with a very different model of reality. Having two models of reality isn’t very convenient, so we have to decide: either this new one or the older one. One has to go. So we have to decide which one is better. How do we do so? Well, simple. The new model of reality is based on everything the old one was based + some more. The fact that the relation between their respective sets of observations is that of relation between supersets and subsets, we can easily conclude the new model of reality is better. (Of course, in reality, this is in most cases just an idealization, since it makes sense that some observations are lost – forgotten – over time.) Anyways, this acquisition of new observations and expansion of the set of observations that serve as the ground for model formation is what gives us the sense of progress and what creates the illusion of “reality that is independent from our minds”. The old model is now seen as an “illusion” and the new one as “truth”. Until the next update, that is. This is also what people mean when they say that there is only more/less true and no absolutely/ultimately true. And also, the fact that this pattern of behavior is not a necessity, that observations are not necessarily accumulated over time, meaning that the set of observations does not have to increase over time, is also the reason behind the existence of movements such as the so-called “relativism” which is in fact egalitarianism. If instead of trying to memorize all of the observations to the best of our ability we end up forgetting many of them such that we end up with sets of observations that are more or less equal in their size but considerably different in their content, we can create the illusion of equality. But that’s another story.
The point is this: there is no such a thing as “reality (or existence, or truth) independent from one’s mind”. That is a meaningless statement taken literally.
And there is absolutely no need to assume that reality exists before we can being modelling reality.