George Berkeley improved upon John Locke's empiricist philosophy by applying Occam's Razor more rigorously. He concluded that we can only know ideas, not any underlying substance. According to Berkeley, all objects are just collections of ideas or sense data in our minds. He believed existence is perception - for something to exist, it must be perceived. Berkeley proposed that God perceives all things at all times, allowing the world to continue existing even when not observed by humans. However, this raised problems for Berkeley's idealism since God cannot be directly perceived.

1. Empiricist Epistemology – John Locke & George Berkeley Unit 3

2. The Empiricism of John Locke Locke disagreed with Descartes’ concept of innate ideas. He sought to create a “simpler” philosophy – through the application of Ockham’s Razor – that would prove Descartes wrong and put forth his own idea of the tabula rasa .

3. John Locke, cont’d… Tabula rasa means “blank slate.” Locke believed that we were all born with a mind like a blank slate – containing NO innate ideas. He asserts that all of our knowledge comes from observation. Ockham’s Razor refers to a principle set forth by William of Ockham stating, “What can be done with fewer [terms] is done in vain with more.” Essentially, when presented with two theories that are both compatible with observable data, the preferred theory will always be the simpler one. See your book, pages 77-78 for an example of Ockham’s Razor in history.

4. Simple and Complex Ideas Simple Ideas are those that cannot be further analyzed into simpler components For example , if your friend does not know what the color green is, you would have to show them a green object, because you cannot further define green. These simple ideas are generally observed by one sense (motion being the one exception) Complex Ideas are: Compounds of simple ideas Ideas of relations Abstractions

5. Primary and Secondary Qualities Primary qualities are characteristics that are necessarily contained within objects Such as: solidity, extension, figure, motion/rest, and number Secondary qualities are qualities that are not contained within objects, but are sensations produced by the primary qualities Such as: color, sound, taste, smell, etc.

6. Primary and Secondary Qualities According to Locke, our ideas of primary qualities are correct ideas. That is, the ideas in our mind correctly represent the way the world is. My perception that the desk in front of me is a rectangle is correct, because the idea of a rectangle in my head lines up with how the atoms (or corpuscles for Locke) are arranged to make up that desk – in the shape of a rectangle. Reality matches the idea in my mind.

7. Primary and Secondary Qualities On the other hand, the ideas we have of secondary qualities are not “correct” in the same way primary qualities are “correct:” they do not necessarily match the external world. Locke says, “The ideas of primary qualities of bodies are resemblances of them, and their patterns do really exist in the bodies themselves, but the ideas produced in us by these secondary qualities have no resemblance to them at all. There is nothing like our ideas existing in the bodies themselves.” John Locke, An Essay Concerning Human Understanding In other words, we may see grass as being “green,” but there is no “greenness” innate in the substance [atoms/corpuscles] that makes up the grass. There are patterns that create the idea of “greenness” in our minds, but the matter itself is colorless.

8. Representative Realism This epistemological view is known as representative realism because it holds that there is an actual world “out there.” This may seem like a given, but as we shall see, not all philosophers believe in the existence of a world outside of the mind. It is called representative realism because, according to this view, the mind does not give us direct access to reality; rather, it represents reality in my the same way that a photograph does.

9. Substance So what is this substance that makes up the world, and creates the sensations of color, scent, sound, etc? Locke says, it is a “thing I know not what.” In other words…He has no idea.

10. The Empiricism of George Berkeley George Berkeley: an Irishman; bishop in the Church of England Saw Locke’s errors, and believed that all that was needed to fix them was a more rigorous application of Ockham’s Razor He concluded, by taking Locke literally, that it is impossible to know something that is not an idea

11. Sense Data Berkeley believed that Locke was contradicting himself when he claimed that the ideas in our mind are caused by things in the physical world. He argued that primary and secondary qualities are actually the same thing (see the table example in your text, page 83) In other words, our ideas of primary qualities are really nothing but interpretations of secondary qualities

12. Sense Data OBJECTS OF HUMAN KNOWLEDGE – It is evident to any one who takes a survey of the objects of human knowledge, that they are either IDEAS actually imprinted on the senses; or else such as are perceived by attending to the passions and operations of the mind; or lastly, ideas formed by help of memory and imagination – either compounding, dividing, or barely representing those originally perceived in the aforesaid ways. By sight I have the ideas of light and colours, with their several degrees and variations. By touch I perceive hard and soft ,heat and cold, motion and resistance, and of all these more and less either as to quantity or degree. Smelling furnishes me with odours; the palate with tastes; and hearing conveys sounds to the mind in all their variety of tone and composition. And as several of these are observed to accompany each other, they come to be marked by one name, and so to be reputed as a thing. Thus, for example a certain colour, taste, smell, figure and consistence having been observed to go together, are accounted as one distinct thing, signified by the name APPLE. Other collections of ideas constitute a stone, a tree, a brook, and the like sensible things – which as they are pleasing or disagreeable excite the passions of love, hatred, joy, grief, and so forth.” George Berkeley, A Treatise Concerning the Principles of Human Knowledge

13. Sense Data Babies come into the world and they are given “sense data” (essentially secondary qualities, colors, sounds, smells, etc). The infant is overwhelmed, as these experiences do not constitute a world for the baby, but rather a “chaos of fluctuating sensations” (according to Palmer). Slowly the child learns to “read” this sense data by recognizing patterns in the appearance of the data ( Note: Rationalists would here question how the baby would recognize patterns without knowing the principles of sameness or identity), and by being taught by their parents

14. If you haven’t noticed…this is radical! Any “physical object” in the world – the chair you’re sitting on, the chicken patty you ate for lunch, the stars outside your window – are merely the totality of its sense data…and sense data exists only in the mind . Esse is percipi …Existence is perception! Physical objects exist only as possible/actual perceptions in the mind…there is no substance!! So, if it’s not being observed, then it doesn’t exist! This view, that contends that only the mental world exists, is called idealism. There is no physical world, if by physical we mean some form of matter/substance that exists apart from some form of consciousness

15. Sense Data -> Knowledge? Because each of us experience these ideas in our own minds, each individual has a different perspective of the sense data. We cannot experience sense data in the same way as other people, as we cannot get inside their minds…we are alone on the island of our minds, awash in the sense data that surrounds us.

16. Sense Data -> Knowledge? So how can society function? If we all have different experiences of the sense data, can there ever be universal knowledge? Language is the bridge that allows us to share knowledge. For example, it is possible that no two people have the same experience when they use such basic terms as the word “red.” But none of this matters practically because even if I see what you call “green” when I look at something “red,” we both describe it as being red because we were taught to associate that particular word (“red”) with that particular experience.

17. The Source of Sense Data So, where does sense data come from? Normally, one would say that sense data comes from “out there,” in the world. But Berkeley and his vigorous use of Ockham’s Razor ruined that for us. How would Descartes and Locke answer the question? They would say that sense data comes from substance/matter, which in turn comes from God Berkeley simply eliminates the middleman. Sense data comes directly from God, he claims! That allows things to continue to exist, even when they are not being observed by any person. God is at all times perceiving all things, which allows the world we inhabit to continue to exist.

18. Problem! How can God exist in a system where esse is percipi? It would seem that either God can be perceived (which we know he cannot, or at least, not in the same way one might observe a carrot or a chicken patty), or that he doesn’t exist. Berkeley was aware of this dilemma, and attempted to escape it by referring to God as a “notion,” rather than an “idea.” Do you buy it?