Editing G. E. Moore (section)

==Philosophy==
===Ethics===
[[Image:Principia Ethica title page.png|thumb|right|The title page of ''Principia Ethica'']]
His influential work ''[[Principia Ethica]]'' is one of the main inspirations of the reaction against [[ethical naturalism]] (see [[ethical non-naturalism]]) and is partly responsible for the twentieth-century concern with [[meta-ethics]].<ref>{{cite SEP |url-id=metaethics |title=Metaethics}} by Geoff Sayre-McCord.</ref>

====Naturalistic fallacy====
{{Main|Naturalistic fallacy}}
Moore asserted that philosophical arguments can suffer from a confusion between the use of a term in a particular argument and the definition of that term (in all arguments). He named this confusion the [[naturalistic fallacy]]. For example, an ethical argument may claim that if an item has certain properties, then that item is 'good.' A [[hedonism|hedonist]] may argue that 'pleasant' items are 'good' items. Other theorists may argue that 'complex' things are 'good' things. Moore contends that, even if such arguments are correct, they do not provide definitions for the term 'good'. The property of 'goodness' cannot be defined. It can only be shown and grasped. Any attempt to define it (X is good if it has property Y) will simply shift the problem (Why is Y-ness good in the first place?).

====Open-question argument====
{{Main|Open-question argument}}
Moore's [[argument]] for the indefinability of 'good' (and thus for the fallaciousness in the "naturalistic fallacy") is often termed the [[open-question argument]]; it is presented in [http://fair-use.org/g-e-moore/principia-ethica/s.13 §13 of ''Principia Ethica'']. The argument concerns the nature of statements such as "Anything that is pleasant is also good" and the possibility of asking questions such as "Is it ''good'' that x is pleasant?". According to Moore, these questions are ''open'' and these statements are ''significant''; and they will remain so no matter what is substituted for "pleasure". Moore concludes from this that any analysis of value is bound to fail. In other words, if value could be analysed, then such questions and statements would be trivial and obvious. Since they are anything but trivial and obvious, value must be indefinable.

Critics of Moore's arguments sometimes claim that he is appealing to general puzzles concerning analysis (cf. the [[paradox of analysis]]), rather than revealing anything special about value. The argument clearly depends on the assumption that if 'good' were definable, it would be an [[Logical truth|analytic truth]] about 'good', an assumption that many contemporary moral realists like [[Richard Boyd]] and [[Peter Railton]] reject.  Other responses appeal to the [[Frege]]an distinction between [[sense and reference]], allowing that value concepts are special and ''sui generis'', but insisting that value properties are nothing but natural properties (this strategy is similar to that taken by [[physicalism|non-reductive materialists]] in [[philosophy of mind]]).

====Good as indefinable====
Moore contended that goodness cannot be analysed in terms of any other property. In ''[[Principia Ethica]]'', he writes:

: It may be true that all things which are good are also something else, just as it is true that all things which are yellow produce a certain kind of vibration in the light. And it is a fact, that Ethics aims at discovering what are those other properties belonging to all things which are good. But far too many philosophers have thought that when they named those other properties they were actually defining good; that these properties, in fact, were simply not "other," but absolutely and entirely the same with goodness. (''Principia'', [http://fair-use.org/g-e-moore/principia-ethica/s.10#s10p3 § 10 ¶ 3])

Therefore, we cannot define 'good' by explaining it in other words. We can only indicate a ''thing'' or an ''action'' and say "That is good". Similarly, we cannot describe to a person born totally blind exactly what yellow is. We can only show a sighted person a piece of yellow paper or a yellow scrap of cloth and say "That is yellow".

====Good as a non-natural property====
In addition to categorising 'good' as indefinable, Moore also emphasized that it is a non-natural property. This means that it cannot be empirically or scientifically tested or verified{{mdash}}it is not analyzable by "natural science".

====Moral knowledge====
Moore argued that, once arguments based on the [[naturalistic fallacy]] had been discarded, questions of intrinsic goodness could be settled only by appeal to what he (following [[Henry Sidgwick|Sidgwick]]) termed "moral intuitions": [[self-evidence|self-evident]] propositions which recommend themselves to moral thought, but which are not susceptible to either direct proof or disproof (''Principia'', [http://fair-use.org/g-e-moore/principia-ethica/s.45 § 45]). As a result of his opinion, he has often been described by later writers as an advocate of [[ethical intuitionism]]. Moore, however, wished to distinguish his opinions from the opinions usually described as "Intuitionist" when ''Principia Ethica'' was written:

{{quotation|In order to express the fact that ethical propositions of my ''first'' class [propositions about what is good as an end in itself] are incapable of proof or disproof, I have sometimes followed Sidgwick's usage in calling them 'Intuitions.' But I beg that it may be noticed that I am not an 'Intuitionist,' in the ordinary sense of the term. Sidgwick himself seems never to have been clearly aware of the immense importance of the difference which distinguishes his Intuitionism from the common doctrine, which has generally been called by that name. The Intuitionist proper is distinguished by maintaining that propositions of my ''second'' class—propositions which assert that a certain action is ''right'' or a ''duty''—are incapable of proof or disproof by any enquiry into the results of such actions. I, on the contrary, am no less anxious to maintain that propositions of ''this'' kind are ''not'' 'Intuitions,' than to maintain that propositions of my ''first'' class ''are'' Intuitions.|G. E. Moore|[http://fair-use.org/g-e-moore/principia-ethica/preface#s0p5 ''Principia Ethica'', Preface ¶ 5]}}

Moore distinguished his view from the opinion of [[deontological ethics|deontological]] intuitionists, who claimed that "intuitions" could determine questions about what ''actions'' are right or required by [[duty]]. Moore, as a [[consequentialist]], argued that "duties" and moral rules could be determined by investigating the ''effects'' of particular actions or kinds of actions (''Principia'', [http://fair-use.org/g-e-moore/principia-ethica/s.89 § 89]), and so were matters for empirical investigation rather than direct objects of intuition (''Principia'', [http://fair-use.org/g-e-moore/principia-ethica/s.90 § 90]). According to Moore, "intuitions" revealed not the rightness or wrongness of specific actions, but only what items were good in themselves, as ''ends to be pursued''.

==== Right action, duty and virtue ====
Moore holds that {{em|right actions}} are those producing the most good.<ref name="Schneewindp153">{{cite book |author=Schneewind |first=J. B. |author-link=J. B. Schneewind |url=https://archive.org/details/companiontoethic00sing/page/153 |title=A Companion to Ethics |publisher=Blackwell Publishers Ltd |year=1997 |isbn=0-631-18785-5 |editor=Singer, Peter |editor-link=Peter Singer |location=Oxford |page=[https://archive.org/details/companiontoethic00sing/page/153 153]}}</ref> The difficulty with this is that the consequences of most actions are too complex for us to properly take into account, especially the long-term consequences. Because of this, Moore suggests that the definition of duty is limited to what generally produces better results than probable alternatives in a comparatively near future.<ref name="Principia">{{cite book |last1=Moore |first1=George Edward |title=Principia Ethica |date=1903 |publisher=Project Gutenberg |url=http://www.gutenberg.org/files/53430/53430-h/53430-h.htm}}</ref>{{rp|§109}} Whether a given rule of action is also a ''duty'' depends to some extent on the conditions of the corresponding society but ''duties'' agree mostly with what common-sense recommends.<ref name="Principia"/>{{rp|§95}} Virtues, like honesty, can in turn be defined as ''permanent dispositions'' to perform duties.<ref name="Principia"/>{{rp|§109}}
 
===Proof of an external world===
{{Main|Here is one hand}}
One of the most important parts of Moore's philosophical development was his differing with the [[idealism]] that dominated British philosophy (as represented by the works of his former teachers [[F. H. Bradley]] and [[J. M. E. McTaggart|John McTaggart]]), and his defence of what he regarded as a "common sense" type of [[Philosophical realism|realism]]. In his 1925 essay "[[A Defence of Common Sense]]", he argued against idealism and [[scepticism]] toward the external world, on the grounds that they could not give reasons to accept that their metaphysical premises were more plausible than the reasons we have for accepting the common sense claims about our knowledge of the world, which sceptics and idealists must deny. He famously put the point into dramatic relief with his 1939 essay "Proof of an External World", in which he gave a common sense argument against scepticism by raising his right hand and saying "Here is one hand" and then raising his left and saying "And here is another", then concluding that there are at least two external objects in the world, and therefore that he knows (by this argument) that an external world exists. Not surprisingly, not everyone preferring sceptical doubts found Moore's method of argument entirely convincing; Moore, however, defends his argument on the grounds that sceptical arguments seem invariably to require an appeal to "philosophical intuitions" that we have considerably less reason to accept than we have for the common sense claims that they supposedly refute. The "Here is one hand" argument also influenced [[Ludwig Wittgenstein]], who spent his last years working out a new method for Moore's argument in the remarks that were published posthumously as ''[[On Certainty]]''.)

===Moore's paradox===
Moore is also remembered for drawing attention to the peculiar inconsistency involved in uttering a sentence such as "It is raining, but I do not believe it is raining", a puzzle now commonly termed "[[Moore's paradox]]". The puzzle is that it seems inconsistent for anyone to ''assert'' such a sentence; but there doesn't seem to be any ''logical contradiction'' between "It is raining" and "I don't believe that it is raining", because the former is a statement about the weather and the latter a statement about a person's belief about the weather, and it is perfectly logically possible that it may rain whilst a person does not believe that it is raining.

In addition to Moore's own work on the paradox, the puzzle also inspired a great deal of work by [[Ludwig Wittgenstein]], who described the paradox as the most impressive philosophical insight that Moore had ever introduced. It is said{{by whom|date=February 2020}} that when Wittgenstein first heard this paradox one evening (which Moore had earlier stated in a lecture), he rushed round to Moore's lodgings, got him out of bed and insisted that Moore repeat the entire lecture to him.

===Organic wholes===
Moore's description of the principle of the [[organic unity|organic whole]] is extremely straightforward, nonetheless, and a variant on a pattern that began with Aristotle:

: The value of a whole must not be assumed to be the same as the sum of the values of its parts (''Principia'', [http://fair-use.org/g-e-moore/principia-ethica/s.18 § 18]).

According to Moore, a moral actor cannot survey the 'goodness' inherent in the various parts of a situation, assign a value to each of them, and then generate a sum in order to get an idea of its total value. A moral scenario is a complex assembly of parts, and its total value is often created by the relations between those parts, and not by their individual value. The organic metaphor is thus very appropriate: biological organisms seem to have emergent properties which cannot be found anywhere in their individual parts. For example, a human brain seems to exhibit a capacity for thought when none of its neurons exhibit any such capacity. In the same way, a moral scenario can have a value different than the sum of its component parts.

To understand the application of the organic principle to questions of value, it is perhaps best to consider Moore's primary example, that of a consciousness experiencing a beautiful object. To see how the principle works, a thinker engages in "reflective isolation", the act of isolating a given concept in a kind of null context and determining its intrinsic value. In our example, we can easily see that, of themselves, beautiful objects and consciousnesses are not particularly valuable things. They might have some value, but when we consider the total value of a consciousness experiencing a beautiful object, it seems to exceed the simple sum of these values.  Hence the value of a whole must not be assumed to be the same as the sum of the values of its parts.