Besides introducing epistemology and metaphysics, I’m going to be using these lectures as an excuse to talk about three of the most important people who were instrumental in getting Western philosophy started. They are:
Socrates (470-399 BCE)
Plato (427-347 BCE)
Aristotle (384-322 BCE)
I will also be mentioning some other figures along the way.
I. Introduction to Epistemology
A. epistemology = df. the philosophical study of knowledge, from the greek episteme, meaning “knowledge” or “scientific understanding”, and –ology,” study of”.
B. Important questions:
1. What is knowledge?
- Is knowledge more than just correct belief?
- If yes, then what?
- How strong does the justification of belief need to be in order for it to be knowledge?
- Does knowledge require certainty?
2. How much knowledge is possible? Can we have any knowledge?
- skepticism = the denial that knowledge is possible
- There are both general and particular forms of skepticism
- general skepticism = no knowledge is within our reach (about anything)
- Particular forms of skepticism deny that we can attain knowledge about some specific area. E.g., a “moral skeptic” is someone who denies that we can have knowledge about morality
The attempt to overcome skepticism (in its various guises) is one of the recurrent themes in philosophy. Socrates suggested that he might be the wisest person in Greece because he alone was aware of his own ignorance. While he wasn’t a complete skeptic, he was quite modest in what he thought he knew, which is typical of philosophical thinking.
3. What kinds of knowledge are there?
One very important distinction:
- a priori knowledge = knowable through pure, unaided reason or “just by thinking about it” (Example: My knowledge that “Either it is snowing or it is not snowing.” — I don’t need to “go check”.)
- a posteriori knowledge = knowable only by having certain particular experiences, particularly sense experiences. (Example: my knowledge that “It is not snowing.”) (Also called empirical knowledge.)
4. Can we have any non-trivial a priori knowledge?
- Most examples of a priori knowledge are trivial (e.g., the snowing example, or things like “If I’m 26 years old, then I’m 26 years old.”)
- Immanuel Kant (1724-1804) believed that the nature of space and time (i.e. that time is linear and that space has three dimensions) is known a priori, as are the truths of ethics (i.e. that it is wrong to commit suicide).
- Most philosophers believe that mathematics can be known a priori.
5. How reliable are the senses? Can we really gain knowledge through them?
- Problems revolving hallucination, optical illusions, etc. cast doubt on the trustworthiness of our senses.
- More radical doubts stem from considering dreaming and/or the possibility of being a “brain in a vat”. How do we know that everything we see, hear and feel isn’t some sort of illusion or dream?
- David Hume (1711-1776): Just because we have observed things as being a certain way, does that mean they always will be? Do we know the sun will rise tomorrow? (Insert chalk-breaking example here.)
6. Which is our primary or fundamental source of knowledge?
- rationalism: the theory that the fundamental source of knowledge is pure reason or unaided thought (or that most knowledge is a priori ). Plato was a rationalist.
- empiricism: the theory that the fundamental source of knowledge is sense experience (or that most knowledge is a posteriori). Like most scientists, Aristotle was an empiricist.
- in the history of philosophy, almost no philosopher has been either a complete rationalist or a complete empiricist; virtually all agree that both sources of knowledge are important. The terms are usually applied to a philosopher depending on which source is stressed in his or her philosophy.
7. As humans, how do we “represent” the world? (These questions can also be considered metaphysical.)
- How do our perceptions and ideas relate to what’s “out there”?
- What does it mean to say that a belief we have is true?
- What does it mean to say our perceptions are accurate?
II. Introduction to Metaphysics
A. metaphysics = df. the attempt to answer the most fundamental questions about the nature of reality, from the Latin, Metaphysica , which literally means “After the Physics”, referring to a book of Aristotle’s that was put immediately after the Physics in an early Latin compilation of Aristotle’s writings
B. Closely connected with ontology = the philosophical study of being/existence, from the Greek ousia, meaning “being”, and -ology, “study of”.
C. Important questions:
1. What is existence? What is being? What is reality? (These are a little too broad to try to answer directly.)
2. What is the basic vocabulary to use when describing what exists?
- One model comes from Aristotle
- basic distinction is between substances and attributes (and perhaps activities)
- A substance is an independently existing thing. Substances have attributes. The table is a substance. Its color is an attribute. The color is not itself a substance, because it cannot exist without the table.
- Two components of a substance: existence and essence. The existence of the table is that it is. The essence of table is what it is (a table).
- Two kinds of attributes: essential attributes and accidental attributes (“accidents”). The table’s essential properties are those without which it could not be the same thing. The table could not be a table without a flat surface at the top. The table could still be a table without being brown.
- Other philosophers have developed other ways of talking about exists.
3. What are the basic kinds of substances?
- Some candidates: matter or physical substance vs. minds or mental/spiritual substances (see below)
4. Do attributes (e.g. beauty) exist independently of the particular things that have them?
- If yes, then how?
- If no, what is the relationship between the beauty of one thing and the beauty of another?
- Plato’s theory of the forms: There is a separate realm of existence in which things like Beauty itself, Goodness itself, etc., exist. These things are called forms. The actual physical flower is only beautiful insofar as it tries to imitate or copy the form of Beauty. However, the beauty of the flower is not Beauty itself. We cannot see Beauty itself. The forms can only be known by reason.
5. What is a person? What sort of substance(s) are we?
- materialism/physicalism: people are only complex material objects; what we call the “mind” is just certain physical processes taking place in the physical brain.
- dualism: a person consists of two distinct substances: a material body and an immaterial mind, spirit or soul, which are capable of separate existence.
- idealism/immaterialism: people are only immaterial minds, spirits or souls; the body and all other material objects are just images in our minds and do not exist independently from minds.
6. What is God? Does God exist? How much of existence depends on God? ( Theology)
7. What is free will? Does it exist?
8. What is a law of nature? What is causation?
9. What is the nature of space and time?