1. Some comments on knowledge

Before discussing the empiricist tradition, it is important to understand a distinction that is often assumed in the philosophical discussion of the nature of knowledge. This is the distinction between belief, true belief, knowledge and truth.

Belief: While there has been and continues to be a great deal of philosophical discussion, especially in the late 19^th and early 20^th century, about the nature of belief and of what constitutes a belief, for now we will note that belief may refer to the psychological state of having a belief or to the semantic content of that psychological state.

Belief as the psychological state of having a belief may be understood as having an opinion. In this sense a belief may be understood as synonymous as an opinion.

Belief as the semantic content of the psychological state of having a belief refers to the psychological state of holding a proposition to be true. A proposition is the meaning content of a statement or an assertion. Propositions are distinguished from statements or assertions because two different assertions can have the same meaning content. Thus, the meaning content of the assertion, “It is raining,” is the same even if one utters a different statement by expressing that meaning content in French, “Il pleut.” Whether one asserts that it is raining in Hindi, Cantonese, or Swahili, one is asserting the same thing. What one is asserting is the semantic content of the assertion. This semantic content is the proposition. Propositions, like assertions, have the property of being true or false.

We all have a vast number of beliefs. Some of these are true and some are false. It is important to note that the possession of a belief has no bearing on its truth. This is shown by the principle of non-contradiction, for any belief has a negation and either the belief or its negation will be true, but not both.

It is either raining or it is not raining.

It cannot both rain and not rain at the same location in space-time.

Thus, “It is raining here and now” and “It is not raining here and now” cannot both be true.

Truth: The mention of true and false belief above brings us to the issue of truth. In the traditional view of truth, which shall serve us for now, a proposition is true if it corresponds to the way things are. The way things are is a metaphysical issue, a question of what is. Philosophers, except a few subjective idealists, agree that one’s belief that something is true does not make it true. This is important when one comes to discuss issues like morality and the existence of God where it seems as though the truth of the matter cannot be determined by reference to sensation or experience. (Which leads to an interesting aside: What would count as evidence for the existence of God? Do, for example, Descartes’ arguments, work and, if so, why?)

On subjective idealism (also called subjectivist relativism or just subjectivism)

It is not uncommon for individuals to claim what appears to be a subjective idealist account of truth. An instance of this is the casual assertion that “everyone has their own truth.” Philosophically this is best interpreted as meaning “everyone has their own beliefs.” Subjective idealists take this assertion one step further. They assert that the way things are is determined by whatever one believes the way things are. This view is usually rejected because it leads to a violation of the principle of non-contradiction. For example, one person can believe that it is raining here and now. Another person can believe it is not raining here and now. However, the principle of non-contradiction shows that it cannot be both snowing and not raining. Therefore, the ways things are cannot correspond to both these persons’ beliefs. One of them must be wrong. If one of them is wrong, then subjective idealism is false.

True Belief: Now we can define true belief as a belief that corresponds to the way things are. My belief that it is raining is true if, at the time and place I have the belief, it is raining. It is a false belief if it is not raining. Having a true belief is not the same as knowing. The concept of knowledge includes some kind of evidence or justification for the truth of the belief. For example, as I write I could believe that it is raining in Buenos Aires, Argentina. If it is raining in Buenos Aires, then my belief is true. If it is not raining in Buenos Aires, then my belief is false. Even if it is true that it is raining in Buenos Aires, I do not know it is raining, for I have not looked at a weather report for the current conditions. It is simply a belief that happens to be true. To use the terminology of logic, having a true belief is a necessary but not sufficient condition for knowledge. In other words, in order to know, one must have a true belief (necessary condition) but having a true belief alone does not give one knowledge (not a sufficient condition).

Knowledge: Knowledge may now be defined as a justified true belief. In other words, one has knowledge when one has good reasons (justification) for holding that one’s belief is true. The view that knowledge is a justified true belief is sometimes called the tripartite definition of knowledge because it says that for there to be knowledge three conditions need to be meet: 1) One must have a belief. This is to say that all knowledge claims must have propositional content. 2) The belief must be true. It must agree with the way things are. 3) The belief must be justified. One must have good reasons for believing the belief is true.

Justification: Much of the discussion in epistemology and early modern philosophy revolves around the issue of what counts as justification. Minimally, it is often claimed that justification must be truth conducive. If truth is agreement between a proposition and the way things are, then the justification must show this agreement. This raises the issue: How does one show this agreement between an assertion and the way things are? This question leads to the problem of the criterion for knowledge arises. This is the problem of what counts as a sufficient justification for knowing. Sometimes this is interpreted as the question of whether, in order to have knowledge, one needs to know that one knows. The obvious problem with the view that to know one needs to know is that it leads to a regress of justification.

The problem of a regress of justification goes like this:

To know one needs to know one knows.

In order to know one knows, one needs to know one knows one knows.

To know one knows one knows, one needs to know one knows one knows one knows.

And so on… ad infinitum (to infinity)

(A series of claims that logical entails an infinite number of other claims is called a logical regress.)

Because of this, it is usually denied that knowledge depends on knowing that one knows. Rather it is asserted that belief must have sufficient justification if it is to count as knowledge, but this leads to the question of what counts as sufficient justification. In response to this it is said that some beliefs are self-justifying. What we will come to know as a priori truths are typically believed to be self-justifying. An example of such beliefs is a tautology, propositions whose predicate contains the same propositional (meaning) content as their predicate: A bachelor is an unmarried man. Such statements can be logically reduced to A=A, which of course tells one nothing about the world. For epistemology the question then becomes: How can one have self-justifying propositions that are not tautologies?

Certainty: For most modern philosophers (philosophers during the time period from Descartes through Kant) one only has knowledge if one is certain. This is not usually seen as a fourth condition for knowledge. Instead, as we saw in Descartes, justification is given by epistemic certainty. When one is not certain one simply has a belief that may be true.

Before doing the next part of this reading watch:

(Note: the last part of this video is concerned with Gettier cases. Wonder about them, but do not worry about them. Gettier cases will not be on the test.)

Then, after watching the video, go over the reading again and then answer and discuss the “Exercises” questions above on the appropriate discussion board.

2. Empiricism

Introduction

Modern Philosophical thought is often seen as a debate between two different approaches to the problem of knowledge. These approaches are characterized as empiricism and rationalism. Rationalism is seen as a tradition that stems from the work of Rene Descartes and it is sometimes called Cartesian rationalism. The Cartesian rationalist is committed to the view that reason is the source or foundation of knowledge. Thus, Descartes claims in his Meditations to be able to derive the foundations for knowledge through the use of reason and reason alone. These foundations for knowledge the series of proposition argued for in the Meditations:

(1) He knows he exists as a thinking thing.

(2) He is a thinking thing.

(3) God exists.

(4) God is no deceiver.

(5) There exists a world of material things outside of his thought.

(6) He has a body as well as a mind.

The most well-known rationalists who followed Descartes are Spinoza and Leibniz.

Opposed to this rationalist tradition is the tradition of the empiricism, or, commonly, British empiricism. The philosophers who created this tradition are called “British empiricists” because most of them were from the British Isles and wrote in English. What unites British empiricists is a commitment to the view that one cannot have substantive knowledge based on reason alone.

Thus, we have the following distinction:

Rationalism: One can have knowledge of the world from reason alone.

Empiricism: Knowledge of the world (or knowledge of facts) must come from experience. Reason is a tool that one uses to combine and compare experiences.

Empiricism is usually seen as beginning with John Locke’s attack, in his Essay Concerning Human Understanding, on innate ideas or ideas that are in the mind from birth. Locke claims that the mind begins as a tabula rasa, or a blank tablet. Experience is then said to write on the tablet of the mind. Given this view, everything that humans can know must be derived from experience. If there is no experience of something, then there can be no knowledge of that thing. These basic claims are accepted by all empiricist thinkers. Following Locke, Berkeley (pronounced bark-lee; the city in California is called berk-lee) and Hume work through the consequences of this basic empiricist commitment to the grounding of knowledge in experience. Berkeley uses empiricism to give what he considers to be a defense of common sense based on empiricist principles. However, Berkeley’s defense of common sense takes him to the counterintuitive conclusion that there are no material things, there are only ideas of things. This view is known as metaphysical idealism. Hume, on the other hand, reasons from empiricist principles to conclusions that seem to go against common sense, such as the view that there is no evidence for the existence of a substantial self and that there is no good reason to believe that events in the world are linked by a causal relation. Hume’s revolution (Hume died in 1776) leads to a rethinking of the whole approach of modern philosophy in the work of Kant. This will be addressed in the next section of this chapter.

The foundations for British empiricism were laid by the thinkers Francis Bacon (1561-1626) and Thomas Hobbes (1588-1679).

Francis Bacon

Bacon attacked what he called “the idols of the mind.” These idols interfere with the ability of human beings to have knowledge. These idols are the

(1) the idols of the tribe

(2) the idols of the den

(3) the idols of the marketplace

(4) the idols of the theatre

(https://plato.stanford.edu/entries/francis-bacon/#Ido)

Bacon’s attack on these various idols amounts to an attack on knowledge that is based on the authority. Bacon advocates that instead of thinking on the basis of authority one ought to use empirical methods to investigate the world and induction to arrive at general conclusions from one’s experiments. Bacon is usually not studied carefully in the study of the modern philosophical tradition because he did not address the basic problems of knowledge discussed by so many in this tradition. He took for granted our understanding of tools of experience, experiment, and induction as tools to knowledge. The main empiricist tradition is founded on a careful examination and elucidation of these tools.

Thomas Hobbes

Hobbes, on the other hand, is carefully studied by contemporary philosophers, but more for his ethical and political philosophy than his epistemic ideas. His great work, Leviathan is considered on of the most important works of political theory. Hobbes was a contemporary of Descartes. Descartes sent copies of his Meditations on First Philosophy to many of the leading scholars of his day. One of these scholars was Hobbes. Descartes then published his Meditations with “Objections and Replies” from Hobbes and other scholars who had responded to his work.

Like Descartes and Bacon, Hobbes was concerned with reforming the means by which knowledge was obtained. Hobbes proposes the method of resolution and composition. This method is analogous to the analytic and synthetic methods of Descartes’ four rules of his method of knowledge.

Descartes’ analytic method (Hobbes’ resolution) is, “divide each of the difficulties I examined into as many parts as possible and as may be required in order to resolve them better.” In other words, when you examine a problem, break the problem down into its most basic parts and address those basic parts first.

Descartes’ synthetic method (Hobbes’ composition) is, “beginning with the simplest and most easily known objects … ascend little by little, step by step, to knowledge of the most complex.” This means that once you solve the basic problems, use your answers to them to move on to the more complex problems.

However, Hobbes does not follow these rules in a systematic way.

Also, unlike Descartes, Hobbes focuses on language rather than ideas. This focus on language becomes an important part of the method of 20^th century analytic philosophers. For Hobbes, all thought begins in experience, in sensation. Sensation leads to what he calls images, and images to imagination and memory. Only that which is experienced can be thought. Thoughts are divided by Hobbes into unregulated thought, which occurs at random and without our control, and regulated thought, which occurs through words. Regulated thought is the search for causal relations.

All thought, according to Hobbes, is always directed towards the fulfillment of a goal, end, or desire. Ultimately, according to Hobbes, we all desire pleasure. Thus, we use words to order our thought so we can understand the word and find the fulfillment of our desire for pleasure. This view, that all good is reducible to pleasure, is called hedonism. All human beings are, in Hobbes view, basically egoistic (selfish) and they all seek egoistic pleasure (desire) and avoid egoistic pain (aversion). For Hobbes, the key to orderly thought is proper definition. It is careful definition that allows a person to think in an orderly way.

Whereas Descartes is a dualist, someone who believes that there are two fundamentally different substances that make up reality, Hobbes is a metaphysical materialist. Metaphysical materialism is a variety of metaphysical monism. Metaphysical monism is the view that there is only one type of substance or stuff that is used to make everything that exists. The metaphysical materialist believes that everything is made of matter. The metaphysical idealist believes that everything is mind, or idea. The dualist believes that there is both mind and matter. Because Hobbes is a materialist, he needs to explain the nature of thought and of mind. This explanation must rely on nothing other than material entities. While he made some attempts to do this, Hobbes never fully developed a philosophy of mind. Some philosophers speculate that Hobbes was an epiphenomenalist. An epiphenomenalist holds that the mind has unique qualities that are caused by physical processes but do not affect physical processes. So, for example, the colors of a rainbow are a direct result of physical processes, but these colors have no effect on the physical world. Color sensation, is a unique mental event and cannot be understood in purely physical terms.

John Locke

Due to his attack, in his Essay Concerning Human Understanding, on the Cartesian theory of innate ideas, John Locke (1632-1704) is considered the true founder of British Empiricism. Locke’s Essay is a long, convoluted yet philosophically profound and fruitful work. It is quite a task to read it beginning to end, but a careful reading of it is an important philosophical education. One may reject much of what Locke has to say, but one will learn a great deal by doing so. Locke’s Essay should be considered as both a psychological and epistemic text. For Locke, these two subjects were much the same. For Locke, to understand what one understands is to understand how the mind works. The core concerns of the Essay are:

What is the origin and nature of ideas?

How one can have knowledge of one’s ideas?

What is the nature of and limits to knowledge?

Thus, when we discuss, for example, Locke’s theory of substance, it is crucial to keep in mind that the issue is not what substance is, but what can be known about substance. This distinction, between what one can know about the world and what is the case in the world is a crucial distinction in understanding modern philosophy. One of the key insights of modern philosophy is that knowing the limits of what one knows and what one can know is an essential dimension of having knowledge.

The source of all understanding is, for Locke, ideas. This is a necessary truth because Locke defines an idea as any object of human thought or understanding. Thus, to understand is to understand ideas.

Ideas have two sources:

(1) Sensation, which is the appearance of external objects as mediated by the sense organs and (2) Reflection, which is one’s experience of how the mind works.

All ideas therefore are derived, according to Locke from experience of either sensations or reflections. An idea of an orange is the product of seeing its color, touching its skin, peeling it, smelling it and then, finally, tasting it. The idea of whether you like oranges is based on your reflection, your observations, about how you feel when you taste an orange.

Given this, it is clear why Locke would attack innate ideas. If all ideas come from experience, and one has no experience, then one can have no ideas. In his Essay Locke takes the main argument for the existence of innate ideas as the argument that there are universal principles that are agreed upon by all mankind. In other words, on Locke’s view, the argument for innate ideas goes:

P1. If all humanity agrees that a rule or principle is true, then that rule or principle is innate.

P2. There are rules or principles that all humanity agrees upon.

(e.g. the Pythagorean theorem^[1])

C. There are innate ideas.

This is a valid argument. Therefore, the only way to argue against the conclusion is to show one of the premises false.

Locke does this by arguing that universal assent counts for nothing with regard to whether an idea is innate. Locke claims that both P1 and P2 are false.

P2 is false, Locke argues, because (1) there may not be universal assent to any given ideas. This includes ideas such as “all triangles have three sides. Locke says that “children and idiots” may not agree with the truth of so-called universally agreed upon rules and principles. For example, do you know that the Pythagorean theorem is true (can you justify its truth?) or do you believe it on authority?

P1 is also false, Locke argues, because (2) universal assent on the part of all rational individuals does not provide evidence for innateness. He argues that this is the case because (a) reason uncovers no new ideas and (b) reason is only a capacity for inference about what is already known. This second assertion is consistent with what Locke says about reflection. In Locke’s view, this means that only analytic truths (statements whose predicate asserts no more than what is asserted in the predicate, e.g. tautologies) can be universally known to be true. Examples of such truths are sweetness is not bitterness and 2 2=4.

This argument, in various variations has been used by generations of empiricists to argue against a variety of rationalist philosophies. We will se it again, in a slightly different form, in Hume. We will also see a rationalist response to it in the work of Kant. At this point we should only observe that most Cartesian rationalists, and certainly not Descartes, did not argue for innate ideas of the sort that Locke attacks. They argued for ideas that are universal to all rational beings. These may not be ideas one is born with. Rather, they are ideas that any rational being will agree to. In light of this, there is good reason to reject Locke’s rejection of rationalism based on his argument against “innate ideas.”

In any case, according to Locke, the source for all ideas is experience. There are, Locke says, two types of experience, sensation and reflection. One only has ideas when one is aware of them. There are no unconscious ideas. All ideas begin as simple ideas. A simple idea is a single appearance or conception. Locke spends a great deal of time discussing the different types of simple ideas and the sources and objects of such ideas. Perhaps the most important distinction Locke makes is between our ideas of primary and secondary qualities.

Primary qualities are the qualities of the things we sense that cannot be separated from the things themselves. Examples of primary qualities: solidity, extension, figure, motion, rest, and number.

Secondary qualities are qualities that come from the sensation of the object of sensation. Examples of secondary qualities: texture, color, taste, tone and odor. Something smells the way it smells only to some smeller. Thus, it is wrong to say that something stinks. Rather, one should say, it stinks to me.

We perform various operations on our simple ideas. Locke says that

(1) we distinguish one idea from another,

(2) we compare ideas to each other,

(3) we combine these ideas,

(4) we name ideas by associating them with sounds and

(5) we frame abstract ideas by isolating specific aspects of our ideas that we find exemplified in many things. Thus, I can compare my idea of the color of a leaf and the color of grass and abstract the general idea or universal green from these two ideas.

Using these operations, we combine simple ideas into complex ideas.

Locke distinguishes between three types of complex ideas:

(1) Ideas of modes: ideas of the ways in which things can be in themselves.

Things have duration, they exist in space, they can move, they have number and color. These qualities of things are qualities they have without any relation to anything else.

(2) Ideas of relations: ideas of things in terms of other things.

Perhaps the most important of these, and one that is the subject of much philosophical discussion, is the idea of cause and effect. Other ideas of relations include identity (the same as), difference (different then), and location (to the right of, below).

(3) Ideas of substance: This is the most abstract of the three modes of complex ideas.

Substance is that which makes a thing the thing that is it. It is the defining essence of the thing that is unique to that thing.

Locke distinguishes substance in general, ideas of particular substances and collective ideas of substance.

Because we identify things as particular things, we need to explain what makes a thing the thing that it is, if we can find this, we have identified its particular substance.

Because things also exist as collective kinds, trees, chairs or COVID-19 the collective substance is what makes each of these things a member of the class, collection, or kind that they are.

Substance in general is that which things that exist possess. It is what they are made off. It is that which existing things have but non-existing things do not have.

If the concept of substance, and especially the concept of substance in general, seems very abstract, it is. Philosophers have struggled with the nature of substance since Aristotle and continue to do so today. For Locke, substance is a necessary thing. It is what makes something some thing as opposed to no thing. However, Locke, consistent with his empiricism, claims we only experience of particular sensations. We have no experience of that which underlies these sensations. Because of this, we cannot know what substance is apart from the things that have it. It is necessary to the understanding but beyond our experience. Thus, it is Locke famously claims, a something, but “I know not what.”

Another idea that, in Locke’s view, we must have but cannot tie to any experience is our idea of a soul. We know of the effects of a soul and, he argues, these effects cannot be the result of any material substance. He concludes that there must be an immaterial soul, but we cannot have any experience of it. This causes a problem for Locke, because, given this, how is one to explain personal identity? Reflection will make it clear that the material body of a person changes in every way through the course of an individual’s life. What then makes a person the person who s/he is? The traditional explanation is that people possess immortal souls and it is the soul that makes one who one is. But Locke says that this explanation does not work since one can have no knowledge of the soul beyond knowledge of its conceptual necessity. This conceptually necessary but unknowable thing cannot be the basis of our how we remain the same person even though all our perceivable qualities change. Because we cannot explain personal identity by reference to an immortal soul, Locke claims that our sense of self is the result of the conscious awareness of the self. We are whom we think about ourselves as being and whom we remember ourselves as being. This is an epistemic notion of the self. Locke is not explaining what the self is. He is saying that, as far as we can know, the self is what we think of the self as being. This notion of the self is a controversial notion that we shall see taken up by Hume.

The above discussion of substance, the soul, and personal identity should make it clear that Locke’s commitment to empiricism forces him to acknowledge some profound limits on what human beings can know. Knowledge of things beyond one’s immediate experience is a very limited form of knowledge. First, knowledge of what is immediately experienced is not knowledge of what is the case. It is knowledge of what one experiences as the case. Thus, I can argue that I can know, with certainty, that I see yellow. However, seeing a thing as yellow does not mean that the thing that I see is yellow. I could have jaundice. I could be dreaming and what I “see” is not real! This means that Locke does not have a solution to Descartes’ doubt. He grants that, if there is a deceiver, our knowledge is of the world as we are deceived into believing it to be.

For knowledge of things beyond immediate experience we must think in terms of universals or general ideas. For example, to know about dogs one must have a general idea of Dog or dogness. One way of understanding these general ideas is that they refer to actual things. These things are called universals and those who argue for the existence of universals are called Platonic realists. This is what Diotima claims in the Symposium. Platonic realists argue that a statement like “Dogs are descended from wolves” can only be a true statement if the statement refers to things (dogs, wolfs) that actually exist. So, they claim, since the statement “Dogs are descended from wolves,” is a true statement the general terms “dogs,” “wolves,” and “descended from” must refer to something. The Platonic realist calls that which they refer to a universal. Locke, like Hobbes before him, is a nominalist. Nominalists deny the existence of universals. General ideas, according to Locke, are formed around words and reflect the way the minds of human beings make sense of the world. All we can every encounter in our thought are our ideas and the combination of those ideas into general ideas built around that category of words called general terms. General terms are simply names that we give to the arrangements of our ideas.

Locke agrees with Descartes that to have knowledge one must have certainty. This means that, for the Locke the emiricist, there are sharp limits on what we can know. We can have knowledge of our experience. We can have knowledge that comes from the comparison of the ideas we derive from experience. We can have intuitive knowledge of our own existence and we can prove that god exists through the cosmological argument and through the need for there to be a cause of our own existence. Regarding other things, we can only have knowledge of them in terms of our sensation of them. These sharp limits on knowledge, herald the beginning of a slide into the skepticism of Hume.

George Berkeley

Bishop George Berkeley (1685-1753) was a Bishop of the Church of England who argued from empiricist epistemology to an idealist metaphysics in order, he claimed, to defend common sense. Berkeley saw himself as using empiricism to argue against some of the conclusions of corpuscular atomism and the Lockean distinction between primary and secondary qualities.

According to the scientific worldview of the corpuscularists (the view of such eminent thinkers as Galileo, Descartes (when he was speaking about the material world), Boyle, Hobbes, and Newton) there exists absolute time and absolute space. Space is a three-dimensional field in which there are atoms (called corpuscles). It is within this space that things move. These notions of absolute space and times allow for a mathematical framework that allows one to measure velocity, motion and force. Thus, the basic characteristics of the world consist of location at a certain, shape, size, mass and movement from one location to another location. These characteristics are the primary qualities of things. Secondary qualities, heat, sound, smell, color, etc. are the result of an organism perceiving the primary qualities. The taste of sweetness occurs when the appropriate sensors in the tongue are stimulated by the appropriately shaped molecules.

Berkeley is opposed to this view because he sees it as contrary to common sense. Common sense tells use that things are as they are perceived. A red truck is really red. Candy is sweet. Skunks stink. Berkeley also argues that things exist as they are independent of our perception of them. Corpusclarism, he argues, violates both of these principles. In the first place, it says that things are not red, we only perceive them as red. Skunks do not stink, we perceive them as stinking. Secondly, Berkeley asserts that according to common sense, things have the qualities they do even when they not perceived. The corpuscularist is committed to arguing that a fire truck is not red on a dark night or when it is in the firehouse and no one is looking at it. Philosophy confuses us by making distinctions that result from confusions about ideas. This confusion, Berkeley holds, eventually leads to skepticism and atheism. In order to be protected from these consequences, it needs to be shown that these denials of what we know by common sense are based on philosophical errors. Berkeley’s work is part of a philosophical tradition that attempts to use philosophy to cure us of the symptoms of the disease of poor philosophy.

Much of this confusion is the result on philosophers use of abstract ideas. Berkeley asserts that abstract ideas are incoherent; they make no sense. Think, he asks, about the abstract idea of red. Clearly it is an idea of a color, for red is a color, but what color is it an idea of? There are many shades of red. Which shade of red is the idea of red? What about one’s idea of person? How tall is person? We have, Berkeley allows, general terms and these general terms refer to a variety of particular things, but there is no abstract idea that corresponds to these general terms. All there is are particular things that we group together by designating them with general terms. The problem with philosophy is that its use of general terms and its belief that general terms refer to abstract ideas makes it forget that there are only particulars. (Like Locke and Hobbes Berkeley is a nominalist.) There are particular things and particular ideas that are caused by specific experiences. Ideas and the things we have ideas of only exist as they are perceived. Esse is percipi. The whole of what we think and can conceive comes from our perceptions. Can, he would ask, you think of something that exists outside of thought?

Berkeley’s argument for idealism both agrees and contradicts our most basic intuitions about the world. We believe that things are as we perceive them to be. Berkeley argues that this intuition is correct. We believe that things have an existence independent of our perception of them. Berkeley agrees with this as well. He is not a subjective idealist. He believes that things exist as objective entities independent of any individual’s perception because they have a real existence in the mind of God. This means he is an absolute idealist. Things exist as they are in the absolute mind of God. However, we also believe that things exist as material entities. Berkeley asserts that this is not the case. He argues that this belief is incoherent. We can only conceive of things as ideas, so it makes no sense to assert that they are other than ideas. It seems that something has to give here. If Berkeley’s rescue of common sense works, we have to give up our belief that things have a material reality independent of their existence as ideas. If, on the other hand, we insist upon the material reality of things that we perceive then the gap between idea, perception, and reality remains and we are stuck, once again, with the old problem of the criterion for knowledge. How do we know that are ideas of things corresponds to the material reality of things. Is the apple red? Is it sweet?

Now, having done this reading, this reading watch:

Then, after watching the video, go over the reading again and then answer and discuss the questions at the start of this section on the appropriate discussion board.