The master argument is George Berkeley's argument that mind-independent objects do not exist because it is impossible to conceive of them. [1] The argument is against the intuitions that many have and has been widely challenged. The term "Berkeley's master argument" was introduced by Andre Gallois in 1974. [2] His term has firmly become currency of contemporary Berkeley scholarship.
In order to determine whether it is possible for a tree to exist outside of the mind, we need to be able to think of an unconceived tree. But as soon as we try to think about this tree, we have conceived it. So we have failed and there is no good reason to believe that trees exist outside of the mind. [3]
When we do our utmost to conceive the existence of external bodies, we are all the while only contemplating our own ideas. But the mind taking no notice of itself, is deluded to think it can and doth conceive bodies existing unthought of or without the mind; though at the same time they are apprehended by or exist in it self. [3]
Berkeley's argument is an attempt to show that materialism or a mind-independent world is logically impossible. [4]
Bertrand Russell among others believed Berkeley's argument "seems to depend for its plausibility upon confusing the thing apprehended with the act of apprehension": [5]
"If we say that the things known must be in the mind, we are either un-duly limiting the mind's power of knowing, or we are uttering a mere tautology. We are uttering a mere tautology if we mean by 'in the mind' the same as by 'before the mind', i.e. if we mean merely being apprehended by the mind. But if we mean this, we shall have to admit that what, in this sense, is in the mind, may nevertheless be not mental. Thus when we realize the nature of knowledge, Berkeley's argument is seen to be wrong in substance as well as in form, and his grounds for supposing that 'idea'—i.e. the objects apprehended—must be mental, are found to have no validity whatever. Hence his grounds in favour of the idealism may be dismissed." [5]
Christopher Peacocke writes that although Berkeley is correct that one cannot imagine an unperceived thing "all that follows is that the possibility of unperceived material objects cannot be established by appeal to what is imagined. It still could be established by some other route". [6]
Some say that criticisms of Berkeley's argument rely on a misinterpretation of it. Berkeley is not asking us to imagine something unperceived but to imagine that there could be something unperceived, which is a more difficult task. [4] Charles Sanders Peirce agreed with Berkeley that "what we think of cannot possibly be of a different nature from thought itself. For the thought-thinking and the immediate thought-object are the very same thing regarded from different points of view. Therefore, Berkeley was entirely in the right" however he criticised his subjective idealism. [7]
Some claim that Berkeley was not making a master argument at all and that what he was actually trying to show was that the substance 'matter' was actually an abstract concept that passed itself off in peoples' minds as an object of immediate experience. Rather than say that the matter cannot exist, the critics claim, Berkeley is saying that it can only exist as an abstract concept and that this abstract concept was conceptually useless. [8]
In philosophy, empiricism is an epistemological view which holds that true knowledge or justification comes only or primarily from sensory experience and empirical evidence. It is one of several competing views within epistemology, along with rationalism and skepticism. Empiricists argue that empiricism is a more reliable method of finding the truth than purely using logical reasoning, because humans have cognitive biases and limitations which lead to errors of judgement. Empiricism emphasizes the central role of empirical evidence in the formation of ideas, rather than innate ideas or traditions. Empiricists may argue that traditions arise due to relations of previous sensory experiences.
George Berkeley – known as Bishop Berkeley – was an Anglo-Irish philosopher whose primary achievement was the advancement of a theory he called "immaterialism". This theory denies the existence of material substance and instead contends that familiar objects like tables and chairs are ideas perceived by the mind and, as a result, cannot exist without being perceived. Berkeley is also known for his critique of abstraction, an important premise in his argument for immaterialism.
Idealism in philosophy, also known as philosophical idealism or metaphysical idealism, is the set of metaphysical perspectives asserting that, most fundamentally, reality is equivalent to mind, spirit, or consciousness; that reality is entirely a mental construct; or that ideas are the highest type of reality or have the greatest claim to being considered "real". Because there are different types of idealism, it is difficult to define the term uniformly.
The problem of universals is an ancient question from metaphysics that has inspired a range of philosophical topics and disputes: "Should the properties an object has in common with other objects, such as color and shape, be considered to exist beyond those objects? And if a property exists separately from objects, what is the nature of that existence?"
The philosophy of perception is concerned with the nature of perceptual experience and the status of perceptual data, in particular how they relate to beliefs about, or knowledge of, the world. Any explicit account of perception requires a commitment to one of a variety of ontological or metaphysical views. Philosophers distinguish internalist accounts, which assume that perceptions of objects, and knowledge or beliefs about them, are aspects of an individual's mind, and externalist accounts, which state that they constitute real aspects of the world external to the individual. The position of naïve realism—the 'everyday' impression of physical objects constituting what is perceived—is to some extent contradicted by the occurrence of perceptual illusions and hallucinations and the relativity of perceptual experience as well as certain insights in science. Realist conceptions include phenomenalism and direct and indirect realism. Anti-realist conceptions include idealism and skepticism. Recent philosophical work have expanded on the philosophical features of perception by going beyond the single paradigm of vision.
The distinction between subject and object is a basic idea of philosophy.
Solipsism is the philosophical idea that only one's mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known and might not exist outside the mind.
In philosophy, a noumenon is knowledge posited as an object that exists independently of human sense. The term noumenon is generally used in contrast with, or in relation to, the term phenomenon, which refers to any object of the senses. Immanuel Kant first developed the notion of the noumenon as part of his transcendental idealism, suggesting that while we know the noumenal world to exist because human sensibility is merely receptive, it is not itself sensible and must therefore remain otherwise unknowable to us. In Kantian philosophy, the noumenon is often associated with the unknowable "thing-in-itself". However, the nature of the relationship between the two is not made explicit in Kant's work, and remains a subject of debate among Kant scholars as a result.
In common usage and in philosophy, ideas are the results of thought. Also in philosophy, ideas can also be mental representational images of some object. Many philosophers have considered ideas to be a fundamental ontological category of being. The capacity to create and understand the meaning of ideas is considered to be an essential and defining feature of human beings.
In metaphysics, phenomenalism is the view that physical objects cannot justifiably be said to exist in themselves, but only as perceptual phenomena or sensory stimuli situated in time and in space. In particular, some forms of phenomenalism reduce all talk about physical objects in the external world to talk about bundles of sense data.
Subjective idealism, or empirical idealism or immaterialism, is a form of philosophical monism that holds that only minds and mental contents exist. It entails and is generally identified or associated with immaterialism, the doctrine that material things do not exist. Subjective idealism rejects dualism, neutral monism, and materialism; it is the contrary of eliminative materialism, the doctrine that all or some classes of mental phenomena do not exist, but are sheer illusions.
In Kantian philosophy, the thing-in-itself is the status of objects as they are, independent of representation and observation. The concept of the thing-in-itself was introduced by the German philosopher Immanuel Kant, and over the following centuries was met with controversy among later philosophers. It is closely related to Kant's concept of noumena or the objects of inquiry, as opposed to phenomena, its manifestations.
In the philosophy of perception and philosophy of mind, direct or naïve realism, as opposed to indirect or representational realism, are differing models that describe the nature of conscious experiences; out of the metaphysical question of whether the world we see around us is the real world itself or merely an internal perceptual copy of that world generated by our conscious experience.
A pragmatic theory of truth is a theory of truth within the philosophies of pragmatism and pragmaticism. Pragmatic theories of truth were first posited by Charles Sanders Peirce, William James, and John Dewey. The common features of these theories are a reliance on the pragmatic maxim as a means of clarifying the meanings of difficult concepts such as truth; and an emphasis on the fact that belief, certainty, knowledge, or truth is the result of an inquiry.
Philosophical realism – usually not treated as a position of its own but as a stance towards other subject matters – is the view that a certain kind of thing has mind-independent existence, i.e. that it exists even in the absence of any mind perceiving it or that its existence is not just a mere appearance in the eye of the beholder. This includes a number of positions within epistemology and metaphysics which express that a given thing instead exists independently of knowledge, thought, or understanding. This can apply to items such as the physical world, the past and future, other minds, and the self, though may also apply less directly to things such as universals, mathematical truths, moral truths, and thought itself. However, realism may also include various positions which instead reject metaphysical treatments of reality entirely.
A Treatise Concerning the Principles of Human Knowledge is a 1710 work, in English, by Irish Empiricist philosopher George Berkeley. This book largely seeks to refute the claims made by Berkeley's contemporary John Locke about the nature of human perception. Whilst, like all the Empiricist philosophers, both Locke and Berkeley agreed that we are having experiences, regardless of whether material objects exist, Berkeley sought to prove that the outside world is also composed solely of ideas. Berkeley did this by suggesting that "Ideas can only resemble Ideas" – the mental ideas that we possess can only resemble other ideas and thus the external world consists not of physical form, but rather of ideas. This world is given logic and regularity by some other force, which Berkeley concludes is God.
Three Dialogues between Hylas and Philonous, or simply Three Dialogues, is a 1713 book on metaphysics and idealism written by George Berkeley. Taking the form of a dialogue, the book was written as a response to the criticism Berkeley experienced after publishing A Treatise Concerning the Principles of Human Knowledge.
In metaphysics, Metaphysical solipsism is the variety of idealism which asserts that nothing exists externally to this one mind, and since this mind is the whole of reality then the "external world" was never anything more than an idea. It can also be expressed by the assertion "there is nothing external to these present experiences", in other words, no reality exists beyond whatever is presently being cognized by that one mind. The aforementioned definition of solipsism entails the non-existence of anything presently unperceived including the external world, causation, other minds, the past or future, and a subject of experience. Despite their ontological non-existence, these entities may nonetheless be said to "exist" as useful descriptions of the various experiences and thoughts that constitute 'this' mind
The primary–secondary quality distinction is a conceptual distinction in epistemology and metaphysics, concerning the nature of reality. It is most explicitly articulated by John Locke in his Essay concerning Human Understanding, but earlier thinkers such as Galileo and Descartes made similar distinctions.
British philosophy refers to the philosophical tradition of the British people. "The native characteristics of British philosophy are these: common sense, dislike of complication, a strong preference for the concrete over the abstract and a certain awkward honesty of method in which an occasional pearl of poetry is embedded".