Bishop George Berkeley
A Treatise Concerning the Principles of Human Knowledge (Commonly called "Treatise" when referring to Berkeley's works) is a 1710 work by the Irish Empiricist philosopher George Berkeley. This book largely seeks to refute the claims made by his contemporary John Locke about the nature of human perception. Whilst, like all the Empiricist philosophers, both Locke and Berkeley agreed that there was an outside world, and it was this world which caused the ideas one has within one's mind, Berkeley sought to prove that the outside world was also composed solely of ideas. Berkeley did this by suggesting that "Ideas can only resemble Ideas" - the mental ideas that we possessed could only resemble other ideas (not physical objects) and thus the external world consisted not of physical form, but rather of ideas. This world was given logic and regularity by some other force, which Berkeley concluded was God.
13 Objections to Berkeley's principles
[edit] Objection 1
Objection: [A]ll that is real and substantial in nature is banished out of the world, and instead thereof a chimerical scheme of ideas takes place.[34] Answer: Real things and chimeras are both ideas and therefore exist in the mind. Real things are more strongly affecting, steady, orderly, distinct, and independent of the perceiver than imaginary chimeras, but both are ideas. If, by substance is meant that which supports accidents or qualities outside of the mind, then substance has no existence.[35] "The only thing whose existence we deny is that which Philosophers call Matter or corporeal substance."[36] All of our experiences are of things (ideas) which we perceive immediately by our senses.[37] These things, or ideas, exist only in the mind that perceives them. "That what I see, hear, and feel doth exist, that is to say, is perceived by me, I no more doubt than I do of my own being."[38]
[edit] Objection 2
Objection: [T]here is a great difference betwixt real fire for instance, and the idea of fire, ...if you suspect it to be only the idea of fire which you see, do but put your hand into it.... [39] Answer: Real fire and the real pain that it causes are both ideas. They are known only by some mind that perceives them.
[edit] Objection 3
Objection: [W]e "see" things... at a distance from us, and which consequently do not exist in the mind.... Answer: Distant things in a dream are actually in the mind. Also, we do not directly perceive distance while we are awake. We infer distance from a combination of sensations, such as sight and touch. Distant ideas are ideas that we could perceive through touch if we were to move our bodies.[40]
[edit] Objection 4
Objection: It would follow from Berkeley's principles that ...things are every moment annihilated and created anew... .[41] When no one perceives them, objects become nothing. When a perceiver opens his eyes, the objects are created again. Answer: Berkeley requests that the reader...consider whether he means anything by the actual existence of an idea distinct from its being perceived."[42] "t is the mind that frames all that variety of bodies which compose the visible world, any one whereof does not exist longer than it is perceived."[43]If one perceiver closes his eyes, though, the objects that he had been perceiving could still exist in the mind of another perceiver.
[edit] Objection 5
Objection: "f extension and figure exist only in the mind, it follows that the mind is extended and figured...."[44] Extension would be an attribute that is predicated of the subject, the mind, in which it exists. Answer: Extension and figure are in the mind because they are ideas that are perceived by the mind. They are not in the mind as attributes that are predicated of the mind, which is the subject. The color red may be an idea in the mind, but that doesn't mean that the mind is red.
[edit] Objection 6
Objection: "[A] great many things have been explained by matter and motion...."[45] Natural science has made much progress by assuming the existence of matter and mechanical motion. Answer: Scientists do not need to assume that matter and motion exist and that they have effects on an observer's mind. All scientists need to do is to explain why we are affected by certain ideas on certain occasions.
[edit] Objection 7
Objection: It is absurd to ascribe everything to Spirits instead of natural causes.[46] Answer: Using common language, we can speak of natural causes. We do this in order to communicate. However, in actuality we must know that we are speaking only of ideas in a perceiver's mind. We should "think with the learned and speak with the vulgar."
[edit] Objection 8
Objection: Humans universally agree that there are external things and that matter exists. Is everyone wrong?[47] Answer: Universal assent doesn't guarantee the truth of a statement. Many false notions are believed by many people. Also, humans may act as if matter is the cause of their sensations. They can't, however, really understand any meaning in the words "matter exists."
[edit] Objection 9
Objection: Then why does everyone think that matter and an external world exist?[48] Answer: People notice that some ideas appear in their minds independently of their wishes or desires. They then conclude that those ideas or perceived objects exist outside of the mind. This judgment, however, is a contradiction. Some philosophers, who know that ideas exist only in the mind, assume that there are external objects that resemble the ideas. They think that external objects cause internal, mental ideas.
[edit] Objection 10
Objection: Berkeley's principles are not consistent with science and mathematics. The motion of the earth is considered to be true. But, according to Berkeley, motion is only an idea and does not exist if it is not perceived. Answer: To ask if the earth moves is really to ask if we could view the earth's movement if we were in a position to perceive the relation between the earth and the sun[49]. In accordance with our knowledge of the way that ideas have appeared in our minds in the past, we can make reasonable predictions about how ideas will appear to us in the future[50].
[edit] Objection 11
Objection: Ideas appear in a causal sequence. If ideas are mere superficial appearances without internal parts, what is the purpose of the complicated causal sequence in which they appear? It would be less effort for objects to appear as ideas with simple exterior surfaces, without so many internal connections. Answer: Scientists should not explain things as though they are effects of causes. The connection of ideas is a relationship between signs and the things that are signified. We should study our ideas as though they are informative signs in a language of nature[51]. If we understand the language in which these idea–signs are used, then we understand how we can produce connections of ideas.
[edit] Objection 12
Objection: Matter may possibly exist as an inert, thoughtless substance, or occasion, of ideas.[52] Answer: If matter is an unknown support for qualities such as figure, motion and color, then it doesn't concern us. Such qualities are sensations or ideas in a perceiving mind.
[edit] Objection 13
Objection: Holy Scripture speaks of real things such as mountains, cities, and human bodies. Holy Writ also describes miracles, such as the marriage feast at Cana, in which things are changed into other things. Are these nothing but appearances or ideas?[53] Answer: Real things are strong, distinct, vivid ideas. Imaginary things are weak, indistinct, faint ideas. Things that people are able to see, smell, and taste are real things.
Newton asserted that time, space, and motion can be distinguished into absolute/relative, true/apparent, mathematical/vulgar. In so doing, he assumed that time, space, and motion are usually thought of as being related to sensible things. But they also, he assumed, have an inner nature that exists apart from a spectator's mind and has no relation to sensible things.[63] He described an absolute time, space, and motion that are distinguished from relative or apparent time, space, and motion. Berkeley disagreed
