History of Philosophy and Christian Thought - Lesson 11

Rationalism and Empiricism

Empiricism teaches that all human knowledge arises from sense experience. Rationalism teaches that some human knowledge does not arise from sense. experience

Ronald Nash
History of Philosophy and Christian Thought
Lesson 11
Watching Now
Rationalism and Empiricism

Platonic Philosophy

Part 6


IX. Rationalism and Empiricism

A. Introduction

1. Square of Opposition

2. Four Propositions

a. A - All S is P.

b. E - No S is P.

c. I - Some S is P.

d. O - Some S is not P.

3. A and O are contradictions.

B. Definition of Rationalism and Empiricism

1. Empiricism - All human knowledge arises from sense experience.

2. Rationalism - Some human knowledge does not arise from sense experience.

C. Tabula Rasa

1. John Locke

2. Innate ideas - Implicit to Explicit

D. Innate Ideas are not person relative.

1. Equality

2. Justice

3. Goodness

4. Truth

5. Existence of God

E. Invisible Ink

1. Aquinas - "Nothing is in the mind that is not first in the senses."

2. Leibniz added - "Except the mind itself."

  • Thales and Anaximander were two philosophers in the sixth century BC that lived in Miletus.

  • Heraclitus and Pythagoras lived into the 5th century BC.

  • Any worldview addresses the subjects of God, ultimate reality, human knowledge, ethics and human persons.

  • Fundamental beliefs of a naturalistic worldview is that nothing exists outside the physical universe and that all things evolved.

  • Plato was a student of Socrates and lived into the fourth century BC. He opposed hedonism, empiricism, relativism, materialism, atheism and naturalism.

  • Plato described the universe as having three levels: the world of particulars, the world of forms, and the form of the good.

  • Plato's view of the universe was dualistic.

  • One of Plato's fundamental arguments is that the human soul is immortal.

  • Evaluation of Plato's arguments and comparison of Plato's philosophy with biblical theology.

  • Empiricism teaches that all human knowledge arises from sense experience. Rationalism teaches that some human knowledge does not arise from sense. experience

  • Aristotle was a student of Plato and lived in the fourth century BC.

  • Aristotle rejected Plato's doctrine of two worlds.

  • Discussion of Aristotelian philosophy as it relates to the incarnation.

  • Aristotle's philosophy as it relates to attributes of God and fundamental assumptions about psychology.

  • Aristotle made a distinction between passive intellect and active intellect.

  • Discussion of the strengths and weaknesses of the law of non-contradiction.

  • Discussion of the nature and substance of matter.

  • Hellenistic philosophy was an approach that was popular from the fourth century BC to the fifth century AD.

  • Stoics were determinists who believed in living according to nature.

  • Hedonism emphasized pleasure as the greatest good. "Eat, drink and be merry for tomorrow we might be dead."

  • Philo's philosophy was based on a synthesis of Stoicism and Platonism.

  • Implicit "Logos" Christianity is an underlying theme in the book of Hebrews.

  • Plotinus lived in the third century AD and is considered the founder of Neoplatonism.

  • Augustine is a Latin church father, is considered by many to be one of the most important figures in the development of Western Christianity.

  • Augustine wrote Confessions as an autobiographical work to record his experience as a sinful youth and his experience becoming a follower of Christ.

  • Augustine wrote to refute some heresies of the day by focusing on the concepts of faith and reason.

  • Augustine writes about the problem of evil and describes evil as the absence of good.

  • Augustine writes to refute Pelagianism by focusing on the biblical teaching about sin.

  • Augustine writes to refute Donatism.

  • The fundamental idea of skepticism is that no one can know anything. Augustine this statement contradicts itself because the skeptic is claiming that you can know that you can't know anything.

  • When Augustine wrote "The City of God," he had a linear view of history.

  • In Augustine's theory of knowledge, he says that eternal reason and human reason are two different levels of reason.

  • Augustine was personally convinced of the importance of divine illumination.

  • The intellectual background of Thomas Aquinas was influenced by the discovery of ancient manuscripts, the rise of universities, the rise of religious brotherhoods and the rise of Muslim philosophy.

  • Aquinas describes faith as whatever a human can know through special revelation, and reason as whatever a human can know outside of special revelation.

  • Aquinas attempts to prove God's existence.

  • Aquinas describes four kinds of law as eternal, divine, natural and positive.

  • The rationalists and empiricists set the stage for Kant and other philosophers of the modern era.

  • Kant argued that moral requirements are based on a standard of rationality he dubbed the “Categorical Imperative."

  • Kants two worlds are the phenomenal world and the noumenal world.

  • Discussion of criticisms and questions about Kant's ideas.

  • Similarities between Kant's ideas and postmodernism.

  • The dialectic is a central idea in Hegel's philosophy.

  • Ideally, Marxism begins with class struggle, then revolution, dictatorship of the proletariat, withering away of the state, and a utopian classless society.

  • Discussion of four faces of Marxism.

  • Nietzsche proclaimed that, "God is dead." His cure was to live life knowing there is no ultimate meaning. Kierkegaard emphasized a worldview based on true faith.

In this class, you will explore the rich history of philosophy and its relationship with Christian thought. The course begins with an introduction to the definition and importance of philosophy in Christian theology. You will then delve into the evolution of philosophical thought from the Pre-Socratic era, through the Classical Greek philosophers, and into the Hellenistic period. As you progress, you will discover how early Christian thought emerged and developed during the Patristic period, with a special focus on Augustine. The class continues with an examination of medieval Christian thinkers, such as Anselm and Thomas Aquinas, and concludes with an analysis of modern philosophers like Descartes, Kant, and Kierkegaard, and their influence on contemporary Christian thought.

Dr. Ronald Nash

History of Philosophy and Christian Thought


Rationalism and Empiricism

Lesson Transcript


I'm going to talk to you about a very important subject. It's the distinction between rationalism and empiricism and in a very important sense, one of the things we've been doing up until now has been preparing you for this great event, which is the words that I will utter over the next 45 minutes. Rationalism versus Empiricism. An introduction to this subject. Many years ago I found that there was significant value in using as a teaching tool, some material developed by Aristotle. Aristotle calls this material the square of opposition. If any of you took a logic course in college, that was a good logic course. That is, it was it wasn't just symbolic logic. You would have learned about this, even though you might not have recognized how valuable it is. Here's how it goes. Aristotle learned that there are four and only four ways of expressing a truth. There are four and only four kinds of basic propositions. Let me write the word proposition on the board. What is a proposition? It is a sentence that has a subject, a predicate and a verb. End up a sentence like this, i.e., a proposition is a form of language that is either true or false. There are many uses of language that are not propositions. For example, a command is not a proposition. If I were to say to you, Please open the door, please shut the door. It would be quite unusual for any one of you to respond. True, right. Or if you're at a wedding and the preacher says, I now pronounce you husband and wife. And somebody in the audience says, True.


[00:02:28] He's probably a post-modernist. I mean, he's clearly out of out of touch. Now, here are the four kinds of propositions that Aristotle talked about. All is P, No S is p, some SE is P, and some S is not p. Let me give you some examples. Consider as a proposition the sentence. All whales are mammals. That happens to be true. No whales are mammals would be this form and that proposition, of course, would be false. Some whales are mammals. Some whales are mammals would be this third variety and some whales are not. Mammals would be this proposition here. During the Middle Ages, I'm led to understand when Marx had no television and nothing else to do. They gave names to these four kinds of propositions. They call this the a proposition. They call this the E proposition, the I proposition and the oh proposition. All of these details are in your text and the appendix to chapter three. Now, there are two possible reasons why monks during the Middle Ages gave these names. One. One possible theory is that they like to play Wheel of Fortune, you know. And one afternoon. What else can you do in a monastery? So one afternoon, after saying, Give me an E, give me an egg. I mean, I give you an old doing that many times with no Vanna White to watch. All right. They they said, hey, those would be good names for our four kinds of propositions. A more likely reason is we got four propositions here for vowels. Why don't we just use that? Now, let us relate these four kinds of propositions to four possible relationships between human knowledge and sense experience, so that over here we would get this view all human knowledge.


[00:04:45] And I'm taking this right from the book. So you, you know, you could just read it there. All human knowledge arises from sense experience. I also add a footnote or two in your text because there are some qualifications that are necessary. You don't have to worry about those qualifications. I think one of the qualifications goes like this All nontrivial human knowledge arises from sense experience. And if any of you really want me to expound on that, I'll be glad to do. That. But then, of course, I can put that on the midterm exam. Just read the footnote. Okay. Now, this here, this proposition right here is the definition of empiricism. Now, remember, I've told you that probably 90% of you, maybe 95% of you were empiricists the day this class began. If you are still an empiricist, then you believe that all human knowledge arises from sense experience. That's your position. You're stuck with it. Okay, now let's look at the proposition. No human knowledge arises from sense experience. Some people might think that if this is empiricism, then this. No human knowledge arises from sense experience. This must be rationalism. But that's wrong. The position is not rationalism, even though it is the extreme rationalism of Plato. This is Plato's position. Plato denigrated sense experience. Plato believed that if anything is genuinely knowledge, then it must not come through sense experience. I'll say a little bit more about that later on. Now, for our purposes, the AI proposition is going to be irrelevant. It just doesn't work. It doesn't fit in here. And that shouldn't worry you. Just forget it. But what is important here is the relationship between the a proposition and the old proposition. Aristotle called this relationship contradiction. The A and the old are contradictory.


[00:07:17] And what that means is this If the A proposition is true, then the old proposition must be false. Unless you're a post-modernist, I'm going to keep saying that. Okay? I'm going to say that. And if the old proposition is true, then the a proposition must be false. They're contradictory. The truth of one entails the falsity, the other, and so on. Now, how do we word the old proposition in this way? Some human knowledge does not arise from sense experience. Okay. Now, if this is the definition of empiricism, then next week, when I ask you to give me the one and only true definition of empiricism, these are the words you're going to give me. Okay. And next week, when I ask you to define rationalism, these must be the words you give me. Rationalism is the belief that some human knowledge does not arise from sense experience. Not only is the old position rationalism. The old position is Nash's position. Okay. Plato is wrong. First of all, let me appeal to your common sense. Clearly when Plato says no human knowledge arises from sense experience, he's playing games with words. All right. We all are aware of lots of things for which our awareness must come through the senses. Do you see the absurdity of saying that we can never know anything through since experience we were just in a room that we knew was too hot, right? I knew that the reason why Plato disparaged sense experience is because he believed that whatever a true object of knowledge is, it must be unchangeable. Okay. But the objects of sense experience are changing all the time. Therefore, they are unfit. This is. These are beautiful sentences I'm giving you. The objects of sense experience are unfit to function as the genuine objects of genuine knowledge.


[00:10:05] The temperature in this building changes from well, in the case of the upstairs room, from from moment to moment. Some things in life are. Some things in life are relative. All right. Temperature is relative. Some things are don't turn me into a relativist, but some things are. Some things are better examples of readiness than other things. So the objects of knowledge must be the forms. Give me credit. All right. All of the kinds of knowledge that you legitimately think are important can fit within my kind of rationalism. Now, I would also argue that if you study the major rationalists in the history of philosophy after Plato, you're going to find that all of them recognize that human beings do have access to important information through their senses. I mean, I'm not going to deny that you know something about a rose when you smell it, when you see it, when you touch it, that sense experience. Notice another thing that's important. If you are an empiricist you are defending, you must defend an all or nothing position. If you're an empiricist, then you must be prepared to show that everything you know has its source in bodily sense experience. But look at my position. All I have to do for my position to be true is for me to come up with one example of human. That's all I need. You've got to prove that everything comes from the senses. I and other great rationalists. And humility is also a characteristic of rationalism. I and other great rationalist. All we have to do is prove one thing. All right? Actually, I can prove a lot of things. A lot of examples of human knowledge that do not rise up from a sense experience. If you want some examples here they are the truths of mathematics, the truths of logic, and all of Plato's higher forms.


[00:12:30] If we harken back to the fiddle, Plato did prove that you can not get your knowledge of the equal itself from sense experience. Plato argued that other kinds of knowledge are independent of sense experience. They are a priori not are posteriori. Okay, unless your mind possesses certain innate ideas which are then which then get jarred or or or become activated or something else as a result of sense experience, you can't know anything, but the sense experience isn't the source of that innate knowledge. That innate knowledge is a part of your created, your created being. Okay. All right. Let's let's carry this a step further and realize that, like a lot of the stuff we do, I'm just helping you take another step towards what will be the last two or three weeks of the course. There were there have been in the history of philosophy some other key words and ideas that have relevance to rationalism and empiricism. I want to introduce you to a couple of those. One of these other notions is a Latin expression called tabula rasa. This Latin expression is is a conviction that must be held by every empiricist. If you're an empiricist, then you believe the following. You believe that the human mind at birth is a blank tablet, a tabula rasa, or if it helps you a whiteboard without any markings on it at all. Okay. Why must you believe that? Because no empiricist can believe in even one innate idea. All I have to do to get my truth is recognize that there is at least one innate idea. And I'll give you some more examples of that later on. So empiricists believe that the human mind is a blank tablet. Probably the major proponent of this view was a British thinker named John Locke.


[00:14:58] John Locke died. Mm hmm. I'm going to guess around 1610. That's not the right date. And the right date is somewhere in your textbook. Early, early 1600s. John Locke argued that you can prove that the human mind as a blank tablet by simply looking at any newborn baby. Just between you and me, this is one of the dumbest sections in any philosophical writing. It's just. Just really bad stuff. Go up to a newborn baby and ask the newborn baby who is sucking his thumb and go on Googoo Gaga. All right. And say, okay, kid, how much is two plus two? All right. And the kid is going to go ga ga goo goo. And if you go back two weeks later, the kid will say, Mama, well, that's not the right answer either. All right. Now, you know what? John Locke concluded genius that he was. He believed that that proves that the baby has no innate ideas. But what John Locke forgot was that no rationalist has ever taught that a newborn baby can answer any question like that. For one thing, you need language skills. All right. John Locke forgot one of the major positions of a rationalist position that the innate ideas are implicit at birth. Not explicit. Are implicit. Not explicit. Now, implicit knowledge is this. It is knowledge that will be present, but it is not knowledge of which anyone is necessarily conscious at the moment. In other words, that implicit knowledge that a child is born with, that implicit knowledge of certain innate ideas may not become explicit for that child until their child reaches the age of ten or 20. And in the case of America's public schools today, there are many young people whose innate ideas never become explicit thanks to the public schools of America.


[00:17:22] I said many. I'm not. I'm. I'm a moderate, right? I'm a I'm a quintessential moderate. So what has to happen in order for any human being to become conscious of these implicit ideas? Answer. Experience. But experience isn't the source of the knowledge. Experience just gets us. Just hopefully brings us to a conscious. Now, some human beings will never become conscious of some innate ideas. You know, some may never become aware of the concept of the equal itself or whatever else. Innate ideas aren't relative. They aren't person relative. If I've got an innate idea you got it to, even though you may not know it yet. All right. First of all, the idea of equality or similarity every one of you has that is an innate idea if it hasn't become conscious in your thinking. After all, I've talked about it yet, you may want to reconsider your choice of a career. No chuckling there. Okay. Here are other examples of innate ideas. Justice, goodness, truth. With each one of those, I'm taking a step towards the edge of the platform here. You want to know one another and eight idea. The existence of God is in a neat idea. Yes, sir. And I'll say more about that. Maybe not so much in this course, but I will in the apologetics course. Listen to me. If if human beings didn't already have, by virtue of their creation in the image of God in an idea of God's nature, it would be impossible ever to prove the existence of God. Why do you have to prove something that's already innate? Because these innate things are not explicit. We need to help. We need to help people come to an awareness of something that is innate. Okay, So anyway, I don't believe that the human mind at birth is a tabula rasa.


[00:19:34] Now, here's a very good example developed by a philosopher as an alternative. It's the idea of invisible ink. It's the idea of invisible ink. Now, back in my childhood, to do an invisible ink, you had to. You had to get some lemon juice. We probably. I'm going to show you how old I am. We probably did not even have bottled real lemon juice back in those days. You know, back in the late thirties, early forties. The only way you could get lemon juice is by squeezing it from a real lemon. Some of you have never seen a real lemon. All right. So you get some lemon juice, you get an old fashioned quill, and you write a message to your sweetheart in the sixth grade. Okay? Your sweetheart in the sixth grade. And you say, I love you. I love you. What movie is that from? I love you. That's some foolish movie. Oh, I know. Singing in the rain. Singing in the Rain, the greatest musical ever, ever made with Gene Kelly and Debbie Reynolds. I love you. I love you. Okay. Then when the lemon juice dries, the ink disappears. See? But because you and your sixth grade sweetheart have a covenant together, she takes this blank piece of paper, runs home with it, and puts it in front of a lighted light bulb, and the heat turns the invisible ink into visible ink. Oh, wow. And she reads it. I love you. I love you. As sixth graders do. So the human mind at birth, a rationalist would reply, is not a blank tablet. It has invisible ink there. But various things must come together to turn that implicit knowledge, that invisible ink into explicit knowledge. Isn't that beautiful? See how I can take the most homely, senseless things? Now, one last example.


[00:21:52] There is a very important Latin expression here. You must memorize this Latin expression. Why? Well, because one thing we're interested in the classics. Okay. Here's the Latin expression. Benny Hill EST an intellect to quote, known for where it in sense of nothing is in the mind that is not first in the senses. Do you know who first wrote this? At least as far as I know. Saint Thomas Aquinas. The 13th century Catholic Empiricist. Yeah. If you're an empiricist, you're right in there with a pagan like Aristotle. And a Roman Catholic like Thomas Aquinas. I mean, you're out of your league if you want to get in with the reform guys. You've got to be a rationalist. Now, I'm pulling your leg a little bit there. Okay. Nothing is in the intellect, the mind, which is not first in the senses. That's empiricism. Now, what a great rationalist named likeness did. I mean, spell his name for Gottfried likeness. He added a few words to this. Except a intellectuals ipse. Now, before I translate the rest of the sentence, once you've memorized this, let me give you some examples of how it can be used. Now, you're not going to run into big bullies because you're going to stay away from places where bullies are. We're talking bikers. None of you go to biker bars or anything like that. But, you know, if if a if a biker gets caught up in road rage with respect to something you've done and, you know, he comes over there with his £260 of fat and his tattoos and everything else. And, you know, you've got a date and you want to impress the date. Here's here's how you is what you do with the biker. You just say knee, heel, body, best in intellect to quote known for where it in sensa exhibit intellect towards it say.


[00:24:39] That'll shut him up cause he doesn't have to say anything before he beats the whole body. But that'll shut him up, won't it? Or maybe a policeman arrests you or stops you, you know. And you think he's done this unfairly? Just say the same thing. He won't know what you're saying. And you'll just feel better. You'll just feel better to be able to express that in Latin. Okay. So nothing is in the mind that is not first in the senses except the mind itself. Our minds are not empty. Tablets are not. We are not born. Devoid of information. The fact is, however, that the information is implicit, not explicit, don't turn rationalism into a caricature of itself. All right.