Rudolf Carnap is among philosophers whose ideas and theories have stimulated an endless debate among scholars and other philosophers. His propositions have attracted both critics and supporters who have examined the philosopher’s theories extensively. In his work, Carnap asserted that explanation and prediction were closely related especially when used to explain universal laws.
Specifically, he stated that laws are applied in scientific and everyday situations for purposes of explaining the known facts and predicting the unknown facts. In his opinion, scientific explanations are either deductive or probabilistic (Carnap, 1966). Prediction on the other hand is presented as a means of testing laws based on constant and careful observations. More specifically, prediction is presented as a mode of seeking accuracy or less falsehoods through the application of a causal hypothesis.
In both prediction and explanation, it is evident that Carnap suggests that one can ascertain the truth through methods that establish regularities using scientific observations. Such observations should then be tested against perceptions that one holds about a subject, in order to determine if indeed the proposition that one holds is right or false (Ruccio & Amariglio, 2003).
Much of the philosophical advances proposed by Carnap depend on prediction and confirming or disconfirming laws based on constant observations. Reading his propositions, one gets the impression that he firmly believed that there were facts that led to the buildup of scientific knowledge. Specifically, Carnap implies that factuality is the quintessence truth, and even goes further to suggest that observations and facts determine the ‘cause’ of things.
He further suggests that facts are different from laws; facts are “statements of singular occurrence,” while laws are “statements of universality that emerge from the comparison and perception of regularity in observations dispersed over time and space” (Ruccio & Amariglio, 2003, p. 17). Through his writings, Carnap suggests that facts and laws have an undeniable link when used in explanations. This is evident in his statement that “[F]act explanations are really law explanations in disguise” (Carnap, 1966, p. 331).
Carnap’s take on Universal Laws
According to Carnap, the systematic, regular, and repetitive observations that people make either scientifically or in their everyday life make up universal laws (Carnap, 1966).
He explains that the laws as identified by scientists are nothing more than the regularities “observed at all times and all places, without exception” (p. 229). To qualify as a universal law, Carnap proposes that an observation must be systematic and regular whenever and wherever it occurs. As such, an observation only qualifies as a universal law only if it does not change depending on circumstances or time.
Carnap makes a distinction between universal and statistical laws by explaining that the latter happens when regularity is only observed in a number of cases. As such, statistical laws as defined by Carnap are those facts based on quantifiable and measurable observations. For example, stating that ripe oranges are usually orange in color is a quantitative statement implying that although most ripe oranges are usually orange, others can be green in color.
Carnap offers another distinction between the Universal and Statistical laws by stating that the former are usually logically easier since they were always the same in the past, are still the same in the present, and will remain the same in future. Statistical laws on the other hand are a bit hard to understand since one would have to quantify them first before applying them in scientific evidence.
How universal laws figure in explanations
According to Carnap, explanations are used to demystify the facts that are already known (Carnap, 1966). For example, seeing that ice is always cold, the explanation theory as hypothesized by Carnap would seek to elucidate why ice cannot be ice without being cold.
Trying to expound on Carnap’s views, Ruccio and Amariglio (2003) notes that the explanation theory presupposes that nature is always right and cannot therefore represent the universal laws. Any discrepancies that may be observed in universal laws are therefore a misrepresentation by the observers or scientists who advance inaccurate descriptions.
Carnap suggests that scientific explanations are possible when the universal laws, initial conditions and a description of a condition or event that need to be explained are present. All three requirements must be available for an explanation to be valid. According to Murzi (2001), explanations are reasonable derivations of appropriate statements from premises, which are based on a set of conditions and universal laws.
Explaining how explanations feature in universal laws, Carnap states that “unless facts can be connected with other facts by means of at least one law, explicitly stated or tacitly understood, they do not provide explanations” (Carnap, 1966, p. 331). This statement by the philosopher suggests that for explanations to be effective, they must be easy enough to understand.
Carnap however notes that there is a tendency to assume that universal laws are common knowledge amongst all people. This assumption makes explanations offered to people who have little or no knowledge about universal laws unsuccessful. To improve their understanding of an explanation, one would have to state the universal law in its totality.
By noting that universal laws are not common sense, Carnap implies that giving comprehensive explanations to people, and expressing the laws in detail, gives them a chance to understand facts. In daily life, such detailed explanations are usually of little relevance. For example, it is a universal law that hitting someone would cause him or her pain. As such, if a person cries because he or she has been hit, people naturally assume that he or she is crying because of the pain.
This is different from universal laws of scientific nature, since not everyone understands them as easily as they do the laws evident in everyday life. Carnap gives the example of how metallic objects expand on heating. Obviously, not everyone knows that metallic objects behave in that manner when heated. As such, any person explaining the expansion of metallic objects on heating would have to expound on the entire “law of thermal expansion” to make the statement comprehensive enough for the other person to understand.
How universal laws figure in predictions
Carnap argues that predictions provide means through which new facts that are yet to be observed can be forecasted. Carnap (1966) states that predictions occur when elementary logic is used to deduce facts that are not known yet. For the elementary logic to be used however, a knowledge situation must exist. The knowledge situation is made up of a “known fact and a known [universal] law” (Carnap, 1966. P. 332). This then sets the stage for a person to apply logic in a given situation in order to derive an unknown fact.
Since universal laws do not change regardless of time, place, or condition, they form a firm foundation for predictions. People can hypothesize based on how they expect specific subjects to interact with universal laws. Their theories (which are pure predictions) are then confirmed based on how the subject interacts with the universal law (Barrett & Stanford, 1998).
By asserting that making correct predictions is possible when universal laws and knowledge about an issue is existing, Carnap supports the notion that making correct predictions is an outstanding quality of science. This is especially the case since prediction is a deductive outcome based on the application of universal laws and appropriate measurements. In Carnap’s own admission, though statistical laws are logically easier like the universal laws, they can still be used in predictions.
The relationship between explanations and predictions
Reading Carnap’s work, one gets the impression that explanations require more that probabilistic generalizations. In fact, providing explanations require one to understand all the conditions that cause an event. Predictions on the other hand are possible even where generalizations are made without accurate facts to back them.
Regardless of the differences between explanations and predictions, they are both related since they contribute towards knowledge. In fact, it is rather evident that as long as people continue craving for more knowledge, both explanations and predictions as defined by Carnap will continue being used as means of filling the information gaps that exist in the society.
The most striking similarity between explanations and predictions are contained in their use in supporting hypotheses. Specifically, an explanation can be used in predictions, while predictions are valid explanations (Barrett & Stanford, 1998). Moreover, the hypotheses used are based on laws that are either universal or statistical. Either way, both explanations and prediction seek accuracy based on causal hypotheses.
The difference between sentences
Evaluating the sentences “All the coins in my pocket tomorrow will be silver” and “all the coins in my pocket tomorrow will have mass” from Carnap’s treatment of laws reveals that two sets of differences between the sentences. To start with, the first sentence is an explanation, while the latter is a prediction.
The second difference is evident in the person’s use of universal laws in the first sentence, and the use of statistical laws in the second sentence. The fact that silver does not change with time is a universal law. This means that if a person has silver coins today, he is sure that they will still be silver coins tomorrow and any other day in the future. The sentence is an explanation because its author is assuming that everyone knows and understands that silver does not change with time.
The probability that mass of the coins can change with time makes the second sentence a prediction, which has an element of universal and statistical laws. The fact that silver has weight regardless of the quantity of silver one has is a universal law that assures the person that the amount of coins he will be having in his pocket tomorrow will still have some mass.
The change in mass would occur if the person used some of the coins to purchase something. In such a case, he or she would still have silver coins in his or her pocket. The coins would still have mass, but the mass would be different from the mass he had in his or her pockets the previous day.
References
Barrett, J., & Stanford, P.K. (1998). Prediction. In J. Pfeifer & S. Sarkar (Eds.), The Philosophy of science: an encyclopedia. New York: Routledge.
Carnap, R. (1966). Theory and Observation. In M. Gardner (Ed.), Philosophical foundations of physics: An introduction to the philosophy of science (pp. 329-343). New York: Basic Books.
Murzi, M. (2001). Rudolf Carnap (1891-1970). Internet Encyclopedia of Philosophy. Web.
Ruccio, D. F., & Amariglio, J. (2003). Postmodern moments in modern economics. New Jersey: Princeton University Press.