The Paradox of Green- Grue in Describing Emeralds

Induction is a scientific method that makes general inferences from particular incidences. When there is consistence of behaviorappearance of a given phenomenon, we generalize that the phenomenon in question is always A, B, C. For instance, the claim that drunk men are generally disorderly is inferred from several observed incidences of drunk men being disorderly. In connection to the issue at hand, it is not surprising, therefore, to generalize that all emeralds are green. Observed emeralds, so far, confirm that indeed they are of the color green, hence all emeralds are green.

However, Nelson Goodman, in his Fact, Fiction and Forecast, argues that this induction is shortsighted, since it ignores the element of time. Terming it the New Riddle of Induction, he notes that current evidence does not necessarily reflect the state of things in the future. In other words, the argument that all emeralds are green is true only insofar as the present and current evidence are concerned. Goodmans refutation of the inductive generalization about emeralds does not refute its truth that they are actually green on the other hand, he suggests that it is too simplistic and narrow, in that it limits knowledge about things to what has already been observed. More precisely, how sure are we that all emeralds will be green forever, and that what we call green is actually their property in terms of appearance By examining the conflicting concepts of grue and green in relation to their usage in describing emeralds, the paper argues that we prefer the term green because of its simplicity and agreement with current evidence.

The notion that all emeralds are green is based on the evidence that we already have, namely our observations. But observations, when generalized, do not project the truth about things, but predicts about their nature. He says, If the problem is to explain how we know that certain predictions will turn out to be correct, then the sufficient answer is that we dont know any such thing (Goodman 62).  It seems that Goodman was arguing from the point of view that current evidence will be outdated at some point in future, and therefore we need time-conscious expressionsterms to describe things, such that it remains true at all times. To this end, he proposed that all emeralds are grue (a derivative of green) if observed before a given time (t) and appear to be green when observed, or appear blue after time t (Goodman 89).

This is the riddle all emeralds observed so far are green, hence grue. Now assume the year 2050 to be time t. After 2050, all observed emeralds, if they appear to be blue, they will be grue as well. The paradox is that there is lack of distinction between green-grue emeralds and blue-grue emeralds. Simply stated, if all blue emeralds after time t are grue, and grue refers to all green emeralds at the same time, then blue and green are essentially the same and one thing, namely, grue. However, we know that they are not blue is not the same as green, yet in Goodmans riddle, they share the quality grue. Once again, it should be emphasized that Goodmans intention in this paradox is not to prove the inaccuracy of grue to describe green and blue, but rather to demonstrate the inaccuracy of induction, in its tendency to generalize things into a singular description on the strength of isolated observations. The bottom line is that if person A is a drunk and disorderly, and B the same, C the same, it doesnt necessarily, and accurately, justify the claim that all drunks are disorderly. The fact of the matter is that persons A, B and C were disorderly as at a given time and location.

Therefore, in Goodmans good reasoning, the correct generalization is to say all drunks are disorderly, if observed before time t and appear to be unruly. Before time t, in this case, will probably mean before they get sober, because beyond that they will not be drunk, and therefore not disorderly. In analogy with the emeralds, it is not guaranteed that emeralds will be forever green, just as a drunk is neither always drunk nor disorderly. But then, we tend to say Jack is a drunk, dont take him serious, even when, at the particular moment of making the statement, Jack is actually sober, and deserves to be taken serious Thus, the several incidences in which Jack has been observed to be drunk is not good enough evidence to conclude that Jack is always drunk, or should never be taken serious there times when Jack is sober. Likewise, the several observations of green emeralds are not absolute justification that all emeralds are green it is possible that at some point, (time t), emeralds will be identified by some other color other than green. Thus, the best way to describe that color, is to include the element of time in the description, which is exactly what Nelson Goodman does with the grue concept.

In his theory of confirmation, David Hume disputes induction from direct observations by noting that generalizations from direct experiences presuppose the Principle of Uniformity (Hume 41). However, the uniformity principle is not always justified. An illustration will be in order. In weather forecasting, dense, dark low-hanging clouds presuppose a heavy downpour. But it doesnt always rain heavily when there are such cloud(proving the weathermans predictions wrong), although sometimes it does, thereby proving the weatherman right. Will emeralds be uniformly green forever

According to Goodman, it is a test of time remember his central principle- x (emerald) is y (grue), if observed before time t (arbitrary) and appears z (green). Hume further argued that generalizations are essentially hypothetical claims, which are based on current evidence. When we say that America will always be the superpower, that is an hypothetical conclusion we draw from current evidence, which can be overturned by future events. Consider the war in Iraqi. The UN said No, the EU and some heavy-weight countries said wait. The Arab world dared Bush to invade, and the world at large cried foul. After everybody else had shouted their grievances, and some terrorist groups issued their usual threats, Uncle Bush went home, corked the guns, oiled the tanks and headed east. A few days later, Saddams neck was in the hang-mans noose. However, it is possible that at time t, a new superpower, say China, will arise and topple the US. In that case, America is a Superpower if observed before time t (now), and is superior to China.

But nothing beats this before the invention of color technology in electronic image transmissions in the late 20th century, all TV sets displayed black and white images. Red, black and blue were all displayed as black, while white and yellow appeared as white. Suppose a person wanted to classify the colors displayed on TV. Inevitably, he could have said, all images displayed on TV are either black or white. That was very true, of course. However, at time t (when color projection was invented), the claim became disputable on the strength of new evidence, since TV sets could now display green, yellow, red etc. If Goodman had lived before t, he would have said that, all images displayed on TV are either black or white, it observed guess right. And how true Therefore, it follows that current evidence, i.e. all emeralds being green might be disputed in future, after time t.

Why then, do we prefer all emeralds are greenas opposed to all emeralds are grue or America is the superpower instead of adding, if observed before time t In Grue Analysis, Richard Swinburne observes that green is a qualitative property that confirms our present observations. On the other hand, grue has a locational element, in terms of spatial-temporal context. Regardless, they both portray the properties of an emerald in their respective contexts. However, the term grue projects conflicting perspectives, i.e. it is not clear whether all emeralds observed beyond time t shall appear to be green or blue. Because of the uncertainty (note the use of if in the definition of grue), we prefer the already proven concept of green to describe all emeralds. It is possible that they could be grue as well, but that quality is only satisfied under circumstances not compatible with the present. In other words, grue is to the future, an unknown time, with improbable conditions, i.e. emeralds observed will be blue after t. That projection to the future does not appeal to our common sense, and is in conflict with what we already know from experience about emeralds all of them are green, as of this very moment.

Nonetheless, this argument is not without shortcomings. The color green is arbitrary, and there is nothing greenish in the color green, just as there is nothing Jackish in the name Jack. Thus, if we all agree to call the appearance of emeralds grue and stick to it, it will serve the same purpose as green. It is at this point that philosopher Ludwig Wittgenstein saves the argument in a phrase simplicity. He noted that the human mind tends towards the simplification of words (Wittgenstein 363). For instance, what we generally call alcohol is a compound with an overwhelming chemical formula. But it serves us better to avoid the mind-boggling chemical name and simply say it by a simpler term. If you were required to spell out the chemical name of the constituents in Heineken every time you purchased one, it will be a laboring experience, so to speak.

Similarly, the term grue suggests a complicated concept about the color of emeralds. It is not convenient to bear in mind always that when you say grue, you are actually referring to color y before time t. Since green refers to what is universally understood as the appearance of emeralds at all times, and the fact that a blue emerald is yet to be observed after time t, we prefer green to grue. In mans search for knowledge, it has been proven repeatedly that simple concepts make more sense than complex theorizations. Long live good old green


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