He wrote that the concept of materialism or substance" had always been " the main pillar and support of skepticism"on which have been founded all the impious schemes of atheism and irrelig ion .. How great a friend material substance hath been to atheists in all ages were needless to relate. when this cornerstone is once removed the whole fabric cannot choose but fall to the ground Berkeley began with Locke's conclusions and went on to prove that substance really doesn't exist! 6 How did the Irish philosopher manage it? He did by agreeing with Locke that the idea of substance(or matter) is merely an assumption on our part; we can never perceive substance directly What we experience and the only things we experience are colors tastes, odors, etc, that But what about the primary qual ities--shape, solid ity, motion/rest, etc.--how do we know about these? We only infer those too, said Berkeley. How do you know the shape of a seashell? You run your fingers over the surface and feel it. Not exactly, Berkeley reminds us; we don't feel it. We only feel our sensations and proceed to assume that matter exists in "seashell"form and that the matter is the cause of our sensations. We further assume that the matter possesses certain (primary )qual ities which we cannot experience directly So far, Berkeley seems to agree with Locke. But where Locke never doubts the xistence of matter(he merely says we can never know it), Berkeley asks: If substance is merely an assumption, then could that assumption be wrong? Suppose the world of material objects doesn't really exist. How could we account for the supposed objects which cause our perceptions? Berkeley concluded that there is an alternative assumption, just as logical as"substance, and far preferable Assume that God exists, and that he places in our minds all the perceptions which we experience. If we are making assumptions about reality to account for our perceptions, why is the assumption of the matter a more reasonable assumption than the existence of God? And if one is a Christian philosopher, doesn't the assumption of a God-source become a more l ikely assumption than a matter-source? This is Berkeley's"immaterial ism"--matter does not exist It is merely a fiction we thought we needed. The universe is composed of interacting minds only, and God is the source of all our perceptions. all the world is merely an interp lay of mental images and images and ideas grandly provided and coordinated by god Therefore, reasoned Berkeley, "to be is to be perceived"--esse est percipi. There are no"real"clouds, rocks, oceans, stars, penguins, or seashells. Such items are but mind-inlages derived from God. Nothing exists, therefore, except when it is being perceive How can we be sure the persistent objects of experience---our homes, friends, the familiar belong ings--will be there"when we want to perceive them? Does the seashell-image flicker off and on, in and out of existence every time we look at it or turn away from it. No, says Berkeley. God is the eternal perceiver, and all images continue to exist in the mind of God. They are always avail able to us for the asking to be experienced as we would. Indeed, comments Will Durant, "no one since PlatoHe wrote that the concept of materialism or "substance" had always been "the main pillar and support of skepticism" on which have been founded “all the impious schemes of atheism and irreligion ......How great a friend material substance hath been to atheists in all ages were needless to relate....When this cornerstone is once removed .the whole fabric cannot choose but fall to the ground ..." Berkeley began with Locke 's conclusions and went on to prove that substance really doesn't exist! 6 How did the Irish philosopher manage it? He did by agreeing with Locke that the idea of substance (or matter) is merely an assumption on our part; we can never perceive substance directly .What we experience _and the only things we experience _are colors ,tastes ,odors ,etc., that is ,the secondary qualities But what about the primary qua1ities--shape, solidity, motion/rest, etc.--how do we know about these? We only infer those too, said Berkeley. How do you know the shape of a seashell? You run your fingers over the surface and feel it. Not exactly, Berkeley reminds us; we don't feel it. We only feel our sensations and proceed to assume that matter exists in "seashell" form and that the matter is the cause of our sensations. We further assume that the matter possesses certain (primary ) qua1ities which we cannot experience directly. So far, Berkeley seems to agree with Locke. But where Locke never doubts the existence of matter (he merely says we can never know it), Berkeley asks: If substance is merely an assumption, then could that assumption be wrong? Suppose the world of material objects doesn't really exist. How could we account for the supposed objects which cause our perceptions? Berkeley concluded that there is an alternative assumption, just as logical as "substance," and far preferable. Assume that God exists, and that he places in our minds all the perceptions which we experience. lf we are making assumptions about reality to account for our perceptions, why is the assumption of the matter a more reasonable assumption than the existence of God? And if one is a Christian phi1osopher, doesn't the assumption of a God-source become a more 1ike1y assumption than a matter-source? This is Berkeley's "immaterialism"--matter does not exist .It is merely a fiction we thought we needed. The universe is composed of interacting minds only, and God is the source of all our perceptions. All the world is merely an interplay of mental images and images and ideas ,grandly provided and coordinated by God. Therefore, reasoned Berkeley, "to be is to be perceived "--esse est percipi. There are no "real" clouds, rocks, oceans, stars, penguins, or seashells. Such items are but mind-in1ages derived from God. Nothing exists, therefore, except when it is being perceived. How can we be sure the persistent objects of experience---our homes, friends, the familiar belongings--wi11 "be there" when we want to perceive them? Does the seashel1-image flicker off and on, in and out of existence every time we look at it or turn away from it. No, says Berkeley. God is the eternal perceiver, and a1l images continue to exist in the mind of God. They are always avai1able to us for the asking, to be experienced as we would. Indeed, comments Will Durant, "no one since Plato