Metaphysics: Things we can know to be true about reality without the scientific method


1. Intelligibility.

When faced with the experience of reality, the fact that things exist (whatever their nature may be), we are presented with the irrefutable fact that insofar as they have an act of reality they are not also their opposite. Ontologically speaking, we do not have a situation where a thing exists and does not exist at the same time. In other-words the very act of reality is fundamentally intelligible.

This is where intelligibility fundamentally begins for metaphysics. It is the evidence that we can apply the principle of non-contradiction to the act of reality universally.

Insofar this is true we can make inferences about what cannot be true in reality, such as we cannot have a square circle in reality, and sometimes by inferring what cannot be true in reality we can also know what must be true under pain of absurdity. But we cannot necessarily know particulars with this method of inference. I cannot know if a particular kind of atom exists, and as such this qeustion would be a job for science since metaphysics can only know very general truths, or if we come to know a particular thing it is because it follows necessarily from what is generally understood.

2. Ontological Causality.

When talking about cause and effect in metaphysics people are not speaking of it in the same sense that science does. The person doing metaphysics is not concerned with the particular relationships between physical things or particularly what they are, but rather is concerned with the relationship between possibility/potentiality and the beingness of any nature.

Because the principle of non-contradiction applies universally, one can know that if there were absolutely nothing it would be metaphysically impossible for something to begin existing for the simple fact that there is absolutely nothing. Because of this it must be true that there has to already be an actual reality before any possibility or potential can become an actual reality. This is what the person doing metaphysics means by cause and effect, and may use terms like “existential cause” or “ontological cause” and may proceed to make categorical distinctions between a things essence and esse like Aquinas.

3. Proving God’s existence/The uncaused-cause.

It’s on this basis that people like Aristotle and Aquinas use the principle of non contradiction and reductio ad absurdum to build a genuine system of knowledge that does not conflict or undermine any other system of knowledge such as physics/science. Metaphysics stands for beyond or after physics, and is not itself a study of physics but rather it is the study of what it means for a thing to exist…


…Aristotle and Aquinas believe that by using the metaphysical-method they can achieve knowledge of the ultimate reality and deduce some of it’s nature as a necessary consequence. I think that is in fact what they have achieved, by showing that in-order for any and all potential/possible beings to exist one requires an uncaused cause, a being that is not itself an actualized potential or possibility and is therefore unchanging. And as such is distinct from the nature of physical reality which is changing and is comprised of actualized potential and possibility.

Metaphysics is not a farce and neither is it relying on assumptions or tautologies to achieve it’s objective knowledge. It proceeds on a solid foundation, and people who have patience and are good at grasping concepts will find that the metaphysical foundations for Aquinas’s arguments are irrefutable.

God bless.


Except for that physics is limited to the study of physical reality. It cannot say anything about non-physical realities or experiences. It can’t even speak to the nature of the numbers it relies on, which are not physical constructs.


Physical reality is the only ontologically existing reality. I have no idea what you mean by “non-physical reality” or how can one “experience” that “non-physical reality” - after all we use our senses (and their extensions) to “experience” something. Numbers have no “nature”. They are abstractions, based upon the physical reality.

There are two branches of epistemology. One is the study of the objective, physical reality, which is based upon observations. It is called the “scientific method”, because all science relies on it. The other one is the deductive, axiomatic system, which is based upon arbitrarily selected axioms. This kind is abstract, it does not rely on empirical verification.

Metaphysics? Bah, humbug!


To give you one example, as in my previous post, numbers

Numbers are not a condition of physical reality. They are not reliant on physical reality to exist, they simple are. One plus One is two, regardless of if there is a physical representation of those numbers we can quantify and study. It is a non-physical reality, and no matter how you phrase or represent it, that reality remains true.

Beyond that, what about beauty? Yes, there are things which seem to commonly induce an experience of beauty;l but beauty itself, as a concept, isn’t a condition of the physical world. It is an experience we cannot quantify.


…ignoring the fact that the scientific method also employs “arbitrarily selected axioms” when evaluating some subject matter.

The scientific community just attempts to hide this fact by changing the label.

You’d call them “brute facts”. They’re actually the same thing.


Numbers are abstractions, they do not exist as ontological reality. In a hypothetical world without any beings who would be advanced enough to conceptualize - there are no numbers. You say that one plus one is two - as if that would be independent of the axioms of mathematics. But the axioms also do not exist, if there is no one to “invent them”.

Beauty is subjective. It is contingent upon the physical characteristics of the observer. And also, beauty is in the eyes of the beholder. Oops, but the concept of the observer presupposes a physical being with some sensory organs.

Metaphysics is empty speculation without an accompanying epistemology. And as soon as there is an epistemological method - which can be used to separate true and false proposition about the proposed “metaphysical reality” - it becomes science.

The basic principles - like the conservation laws - are not arbitrary, they come from observation.


Sorry, I’m going to have to disagree. “One” exists, regardless of whether or not we observe it. We observed that by putting one thing together with another, we have two things. The concepts of one and two are not dependent on the existence of the thing, but rather the things expresses the realities of one and two which exist independently of them.

Regardless, that is a philosophical position you are putting forward, not a scientific one. That means that it falls under the topic of metaphysics. By attempting to disprove my point, you are actually proving it. It is an abstract concept that numbers are an axiom of our creation, just as it is an abstract concept that they exist independent of our observation of them.

I’m not talking about what individuals find beautiful, but rather the subjective experience of beauty. The sensation of beauty, the reason we interpret things as beautiful, and the reason that certain things seems to be beautiful regardless of external influences. Chemical reactions in the mind can explain certain emotional reactions, but they cannot explain why our brains react the way they do to things which we find beautiful.

Once again, that can only exist for those things with physical expressions and characteristics. Despite your efforts to deny it, your own arguments against my position rely on presuppositions about the nature of things like number which are not themselves verifiable. Your opinion on the nature of numbers is as metaphysical as my own.


Quite right.
The presupposition here is a mechanical view of the universe and a mathematical description of reality. There is no denying that this ‘scientific method’ has brought lots of technological advances but it is fallacious to infer from that to the falsity of Aquinas’s approach.
What he was doing is attempting to get at the deep ontological structure of reality, which the mechanical-quantifictional scientific method has little to nothing to contribute to. Aquinas’s reality is one where existence has meaning it is not just a brute fact.


No one said it could. Did you read the OP? It doesn’t seem as if you did, otherwise you would have addressed it if you were interested in anything more then throwing insults at something you don’t want…

I respect science for what it can tell us about the particular behavior and nature of physical things. But if you want to refute metaphysics you are going to have to demonstrate why the OP is wrong as opposed to merely asserting that metaphysics is just a flawed alternative to physics. You seem to really think that such an ignorant view is true, which leads me to believe that you have simply ignored the OP, and instead of actually refuting my claim you have chosen to tell us tales about your wondrous assent to a fallacious philosophical point of view called scientism.

If you have a real argument, make one.


Science doesn’t tell us that. This assertion is just a belief that you have, right? Or perhaps you meant that physical reality is the only reality that we scientifically know about. That would at least be a reasonable thing to say.


There is certainly room for thought experimentation…it’s primarily how Eisenstein’s Theory of Special Relativity came about as I understand… However numbers are not really our invention. The specific system we have to describe them is certainly.

There is and always have been differences between things, what math attempts to quantify. Math is our primary tool for discovering how the universe works. The days of science through haphazard direct observation as a primary method is kind of over. We now develop mathematical models and use them to predict what we expect to see. If it was not the fundamental way we can describe what we know, then I think we’d have an argument for science being removable from the description of reality.


You are playing fast and loose with the word “exists”. There is “physical, tangible existence”, which is experienced by our senses - and it exists even if there is no one to observe it. There is “abstract existence”, which may or may not depend on the physical reality. (Some concepts are totally invented.) But abstractions require a sapient being who is able to perform abstractions.

What you assert is identical to the concept of abstract objects, which are assumed to have mind-independent existence. (A concept propagated by Plato) The usual reference to numbers - as very simple abstractions - is touted as a reasonable approach. The proponents assert that numbers are not “created”, rather discovered.

However, it is child’s play to show that there are no objectively existing “abstract objects”. Take the book of “War and Peace”, or the “Ninth Symphony”, neither of which are objectively existing entities, which had to be “discovered”. (Don’t confuse the book with the actual concept.) Before their authors created them, they did not exist in any sense of the word. If, due to a catastrophe, the whole Earth would be scorched by the Sun going nova, they both would cease to exist.

Abstractions do not have mind-independent existence. Now, the “attribute” of “one” does exist whether there is anyone able to observe it, but the “concept” of one requires a functioning mind to conceptualize it. Of course there is no attribute of sqrt(-1), which would exist without an observer. We invented the extrapolation of the number line and created the complex number plane, just for the fun of it.

The major problem with your approach is that you confuse the “attribute” of “one” with the “concept” of “one”. Until you realize this difference, there can be no meaningful conversation.


Observation (the first “leg” of science) makes it a plausible starting point. If anyone discovers some alternate “reality” then we shall have to re-assess this principle, and incorporate the new discovery.


When a mathematical realist states that “1+1=2 exists,” they aren’t saying it is spatialtemporal or capable of causing anything or floating around in any quasi dimension . They just mean there is a type of reality to it such that it is an objective truth and not just a subjective human invention that has no grounding in objective reality.


Does it? The scientific method cannot test the purpose of an eye, yet in biology and medicine it is common to speak of it as having a purpose of seeing (relaying EM sensory data to the brain). But there is no strictly empirical way to test for purpose. Neither can the scientific method alone strictly measure or detect perceptual experiences. Neither is there any strictly empirical way to test ethics. Yet we can, through observation and reason, make qualitative conclusions about properties that can’t be measured.

The point here isn’t even about whether the eye has a purpose. The point is that the scientific method, by definition, is incapable of measuring qualitative properties of the physical world, if there are any. It’s not something the scientific method would ever be capable of measuring. It’s not simply a matter of needing more technology. That doesn’t mean there is any such thing as the qualitative.


Because it’s purely theoretical, although one can make the argument that having the correct knowledge will assist one in making rational choices and deliberations that lead to correct actions.

  1. Pain and suffering are perceptible to the senses, and learned by the intellect.
  2. Building on that, pain has an identifiable cause - as do truth and beauty. This “should” lead us closer to God.
  3. “Proof” is demonstrated at our judgment, when no one will deny the reality of God. Until that point, some degree of faith is required.


You can’t speak about metaphysical-naturalism and then say you are doing science. Science is silent on what other natures there may or may not be. If you want to believe that physical reality is all there is, then that is your belief and you are welcome to it.


Your entire refuting argument, of books, is like comparing apples and oranges. Letters and numbers are not the same thing.

Letters are derived from a cultural understanding of how to construct language. They are physical representations of sounds we have ascribed meaning to. They have no inherent aspect to them which requires that a given letter be associated with a given sound, idea, etc.

Numbers are different. No matter how you represent it, One plus One will always be Two. Whether you represent it with words, sticks, atoms, sign language, or mere though, one plus one will always be two irrespective of the form those abstracts are given by the people observing them.

The two things are ontologically different.

Also, just a small note, your argument that numbers only exist when observed is itself an abstract philosophical position. It’s unprovable. Yes, number certainly exist when they are observed, but when you’re not there to observe them you cannot know whether they exist or not. Your argument relies on an unprovable philosophical position, which is the very problem you seem to have with metaphysics as a branch of study.

You’re right that this conversation isn’t going to be fruitful for either of us, but I would disagree with why that is. The attribute of one and the concept of one both derive from the reality of one, which exists regardless of whether or not it is observed. We can know this implicitly because the laws of physics rely on these abstract realities to function, but the laws of physics were functioning long before there was anything around to observe them.

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