What is Metaphysics?

Metaphysics is the study of the most basic principles of reality, the ultimate structure of things, or as the ancient Greeks would say “first principles.” The goal of metaphysics is to find out the truth about the basic nature of reality, to determine what kinds of things exist and what things do not exist and how they relate to each other. Generally, the kind of stuff that Aristotle was concerned about when the wrote his Metaphysics. (Thomson, 265)

One way to conceptualize metaphysics is to say that science typically seeks to describe “how” things work, but metaphysics focuses upon “what” kinds of things exist, what it means for them to exist, and the “why” questions concerning these things. (Ney, 31-36).

A primary concern of metaphysicians is what it means for something to “exist” and what kinds of things exist. Ancient metaphysicians often relied upon reason, intuition, trances, dreams, and the study of nature to draw conclusions about how reality is structured. Plotinus practiced divination and an entire section of his Enneads (3.4) is dedicated to Tutelary Spirits.

Nowadays, metaphysicians rely primarily upon the tools of logic and insights gained from scientific discovery to go about their research. In the past century great discoveries have been made by physicists concerning the nature of space, time, causation and the nature of reality at the microscopic scale. These are of great interest to metaphysicians, who are often concerned with the nature of physical things, free will, time, and how they relate with one another.

A great deal of modern metaphysics is about whether anything exists beyond the natural or physical world. Some philosophers think there are abstract objects (such as mathematical objects) in addition to physical things. An abstract object, would be one which exists but is not extended in space, something which has properties but does not have any physical properties like location, weight, or mass. Some philosophers think that the mind is an immaterial substance (substance dualism) or that there is a God of some sort. If real, such things would exist beyond the physical world in some sense.

In metaphysics, claims about reality are supported by arguments because no direct proof is often available. The premises of these arguments are usually supported by claims about possibility, impossibility and necessity (i.e. modality). Claims about the way things could possibly be, how they could not possibly be, and what things must always be the case. Also scientific evidence is sometimes used to support premises and metaphysical arguments or appeals to intuition. Modern philosophers do not usually make appeals to dreams, mystical experiences, or visions (like Socrates, etc.). (Apology, 21b-d, et al) 

A Basic Introduction to Logic

The primary tool of philosophers is logic, essential to construct arguments and analyze concepts. The field of logic is the systematic study of the principle of valid reasoning. If philosophy is going to arrive at the truth of anything, it requires methods to arrive at the truth. There is nothing more fundamental.

An argument in philosophy is a series of statements or claims which are presented in support of a particular conclusion. A premise is a statement in the argument that leads to the conclusion. There are two basic kinds of arguments, deductive arguments and inductive arguments. The most common example of a valid argument is:

1. All men are mortal.

2. Socrates is a man.

C. Socrates is mortal.

This is an example of a deductive argument. Deductive arguments are arguments which are intended to reason from general principles to specific conclusions. In a valid deductive argument, if the premises are true, then the conclusion must also be true. An argument is sound if and only if, it has true premises and a valid form. It is possible for an argument to be valid and yet unsound.

It is impossible for the premises of a deductive argument to be true, yet for the conclusion to be false. If the first two premises of this example argument are true then the conclusion is entailed by logical necessity. If all men are mortal and Socrates is a man, then it cannot be the case that “Socrates is not mortal.”

This example argument is also a kind of Categorical Syllogism. A syllogism is a formal argument with numbered or otherwise ordered steps and a conclusion. It is called a categorical syllogism because it reasons about categorical claims, i.e. about the category “men.”

Inductive arguments differ in that they argue from specific observations to a more general conclusion. They include probabilistic arguments, and they seek to make probable conclusions about the world from some set of data which seems to favor the conclusion.

1. About 99% of all species that have ever lived on earth are now extinct.

2. Canis familiaris is a species that has lived on Earth.

C. Therefore, the species canis familiaris is extinct.

The conclusion of this inductive argument is factually wrong, canis familiaris refers to dogs, which are quite common nowadays. Hence, this is an unsound argument. But, it is not an invalid argument. Both of the premises are true and yet the conclusion is false. This illustrates that inductive arguments do not lead to certain conclusions. It is possible for all the premises of an inductive argument to be true and yet for the conclusion to be false—this is unlike deductive arguments, where, if the premises are true then the conclusion cannot be false.

Abductive arguments are sometimes set as a third class of argument (some authors include them as a subset of inductive argument). These are inferences to the best explanation. Most of our daily reasoning may be considered abductive. Consider, when someone sits down in their favorite chair it is because they trust that the chair will be stable when they sit in it. Very rarely do people first test the stability of the chair. It is often possible that someone filed down the legs of the chair or otherwise rigged the chair to collapse when anyone attempted to sit in it. But the chair was stable in the past, and the chair looked fine upon cursory glance, so people tend to sit in their chair and often are right in their belief that the chair will be stable when they sit in it. They make an abductive inference that the chair will not collapse once they sit in it. An example of an abductive argument would be:

1. There are cell phones in the world.

2. Humans tend to make cell phones.

C. All cell phones are made by humans.

It is possible that there is a cell phone made by an artificial intelligence, or an alien or by some unknown process. But the best explanation for all the cell phones in the world is that humans have made them. This is the simplest explanation, consistent with what is usually true about cell phones, as stated in premise 2. Many would even think it “crazy” to deny the conclusion of the argument without some strong evidence of non-human cell phone makers. Why is this the “best explanation”? What constitutes a “best explanation?” This depends upon the standards of explanation, justification, and other criteria that the reasoner has in place. But generally, and in our everyday life, explanations are good insofar as they are simpler than rival explanations, explain the data under consideration, and are consistent with our background knowledge.

Symbolic logic is a way of talking about logical expressions and structures without using traditional language. It allows for more precise expressions of logical formulas than vernacular speech. Consider again the following example:

1. All men are mortal.

2. Socrates is a man.

C. Socrates is mortal.

It is possible to symbolize this argument in the following way, if we let M(x) = “x is mortal” and H(x) = “x is a man” and s = “Socrates”

1. ∀x(H(x) ⊃ M(x))

2. H(s)

C. M(s)

The subjects are substituted with variables or letters and operators or adjectival expressions are substituted for symbols. For example, ⊃ means “then” or “entails.” The symbol ∀ means “all” or “for every.” To say “∀x” is then, to make a claim about all x’s i.e. about anything which is an x. The parentheses are used to divide up the expressions and organize them, so we know the full range of applications for the expressions given i.e. it groups things together for us.

What is Philosophy?

The English word philosophy is derived from the Greek φιλοσοφία (filosofia) which means love of wisdom. Webster’s dictionary gives a definition of philosophy which is too broad to apply to the academic study of philosophy, “all learning exclusive of technical precepts and practical arts.”

The Platonic dialogue, the Euthydemus says “philosophy is the possession of knowledge; and knowledge must be of a kind which is profitable and may be used.” In the early days of the scientific era, the now separate fields of chemistry, biology, and physics were together labeled as “natural philosophy” because they sought to gain wisdom about the natural world. Nowadays, we make a distinction between “science” and “philosophy.” Bertrand Russell considered philosophy to be the study of the uncertain, an attempt to gain clarity on those facts which are outside the reach of science. On one occasion, Russell said “science is what we know and philosophy is what we don't know.”

Nowadays, modern philosophers generally like to think that their work leads to knowledge of something and is practically useful. Academic philosophers often wish their work to be practical rather than abstract, and their theories to be natural rather than spiritual. Since Karl Popper, it is especially fashionable for philosophers to desire their work to be beneficial to science. Modern philosophy refers to an academic study of the nature of reality, existence, the mind and knowledge—it is a quest to understand the truth about the most general features of the world. It considers questions like “What is existence?” “Is there a God?” “What is consciousness?” “What is the nature of moral values?”

Introductory Philosophical Resources:

Stanford Encyclopedia of Philosophy 

Routledge Encyclopedia of Philosophy 

Internet Encyclopedia of Philosophy 

Perseus Digital Library (Tufts University)

The Internet Classics Archive (MIT)