Descriptive knowledge
5046664
221803267
2008-06-26T04:42:41Z
74.12.220.83
/* Knowledge in science and engineering */
{{unreferenced||date=September 2007}}
'''Descriptive knowledge''', also '''declarative knowledge''' or '''propositional knowledge''', is the species of [[knowledge]] that is, by its very nature, expressed in declarative sentences or indicative propositions. This distinguishes descriptive knowledge from what is commonly known as "know-how", or [[procedural knowledge]] (the knowledge of how, and especially how best, to perform some task), and "knowing of", or knowledge by acquaintance (the knowledge of something's existence).
The difference between knowledge and beliefs is as follows:. A [[belief]] is an internal [[thought]] or [[memory]] which exists in one's [[mind]]. Most people accept that for a belief to be knowledge it must be, at least, [[true]] and [[justified]]. The [[Gettier problem]] in philosophy is the question of whether there are any other requirements before a belief can be accepted as knowledge.
The article [[Knowledge (philosophy)]] discusses the view of philosophers on how one can tell which beliefs constitute actual knowledge.
==Acquiring knowledge==
People have used many methods to try to gain knowledge.
# By [[reason]] and [[logic]] (perhaps in cooperation with others, using [[logical argument]]).
# By [[mathematical proof]].
# By the [[scientific method]].
# By the [[trial and error]] method.
# By applying an [[algorithm]].
# By learning from [[experience]].
# By an [[appeal to authority|argument from authority]], which could be from religious, literary, political, philosophical or scientific authorities.
# By listening to the [[testimony]] of [[witness]]es.
# By [[observing]] the world in its "natural state"; seeing how the world operates without performing any experiments.
# By acquiring knowledge that is embedded in one's [[language]], [[culture]], or [[tradition]]s.
# By dialogical enquiry (conversation). See Gadamer, [[Bohm Dialogue|Bohm]], Habermas, Freire, on dialogue, learning and knowledge acquisition/negotiation: http://www.infed.org/biblio/b-dialog.htm
# By some claimed form of enlightenment following a period of [[meditation]]. (For example, the Buddhist enlightenment known as [[bodhi]])
# By having a [[divine illumination]] or [[revelation]] from a divine agency.
== Types of knowledge ==
Knowledge can be classified into [[a priori and a posteriori (philosophy)|a priori]] knowledge, which is obtained without needing to observe the world, and a posteriori or [[empirical knowledge]], which is only obtained after observing the world or interacting with it in some way.
Often knowledge is gained by combining or extending other knowledge in various ways. [[Isaac Newton]] famously wrote: "If I have seen further... it is by [[standing on the shoulders of giants]]".
Inferential knowledge is based on [[logic|reasoning]] from facts or from other inferential knowledge such as a [[theory]]. Such knowledge may or may not be [[verification|verifiable]] by observation or [[Experiment|testing]]. For example, all knowledge of the [[atom]] is inferential knowledge. The distinction between factual knowledge and inferential knowledge has been explored by the discipline of [[general semantics]].
== Knowledge in various disciplines ==
There are many different disciplines that generate beliefs that can be regarded as knowledge. They include science (which generates scientific theories), law (which generates verdicts), history (which generates history), and mathematics (which generates proofs).
=== Knowledge in science and engineering ===
[[Scientist]]s attempt to gain knowledge through the [[scientific method]]. In this method, scientists start by finding a phenomenon of interest, which generates questions. A scientist then picks a question of interest, and based on previous knowledge, develops a hypothesis. The scientist then designs a controlled [[experiment]] which will allows him to test the hypothesis against the real world. He then makes predictions about the outcome of the test, based on the hypothesis.
At this point, the scientist carries out the experiment and compares his predictions with his observations. Assuming that there were no flaws in the experiment, then if they match, this is evidence in favour of the hypothesis. If they do ''not'' match, then the hypothesis has been [[falsifiability|falsified]]. The next steps are [[peer review]] and publication, through which the results are distributed to other scientists.
A hypothesis that has been shown to accurately and reliably predict and characterize some physical phenomenon, and has been sufficiently peer-reviewed and tested, may become a [[scientific theory]]. Scientific theories are widely regarded as knowledge, though they are always subject to further revision or review should new data come to light.
To use scientific theories, they must be applied to the specific situation in hand. For example, a [[civil engineer]] might use the theory of [[statics]] (a branch of [[physics]]) to determine whether a bridge will hold up. This is one case where new knowledge is generated from scientific knowledge by [[specializing]] it to an individual instance.
=== Knowledge in history ===
The scientific method does not apply to [[history]] (or related disciplines, such as [[archeology]]), because it is not possible to ''construct'' experiments to test theories. Suppose a historian believes that [[Napoleon]] would have won the [[Battle of Waterloo]] if [[Gebhard Leberecht von Blücher]] had arrived an hour later. The historian cannot simply re-run the battle and see what would happen with different [[starting condition]]s.
Additionally, the scientific method is essentially the application of the inductive approach to investigation. This approach is entirely appropriate for exploration of the causal world of nature (physics, chemistry, etc.) but not valid for the teleological social sciences, which includes history. There are no constants in human relations, only unmeasurable and inconstant subjective valuations. Electrons always behave the same way under the same conditions, but humans do not -- different people seem to react differently and the same person seems to or might react differently at different moments in time. Thus, it appears that only spurious inferences can be drawn from repeated observations of human behavior. It might be observed that most humans prefer wealth to poverty or life to death, but it might be invalid to infer any universal law of human behavior from this.
Historians often generate different [[historical interpretation|interpretations]] of the same event, even when reading the same [[primary source]]s, and these interpretations are always subject to [[historical revisionism|revision]] by other historians. This is because, as a social scientist, the historian must constantly make subjective judgements of relevance in trying to interpret historical events.
Sigmund Freud said that there was another knowledge. The knowledge you have in dreams, which are wishes you want to come true
== Situated knowledge ==
From [[Knowledge#Situated knowledge|Knowledge]].
Situated knowledge is knowledge specific to a particular situation. Imagine two very similar breeds of mushroom, which grow on either side of a mountain, one nutritious, one poisonous. Relying on knowledge from one side of an ecological boundary, after crossing to the other, may lead to starving rather than eating perfectly healthy food near at hand, or to poisoning oneself by mistake.
Some methods of generating knowledge, such as trial and error, or learning from experience, tend to create highly situational knowledge. One of the main benefits of the scientific method is that the theories it generates are much less situational than knowledge gained by other methods.
Situational knowledge is often embedded in language, culture, or traditions. Critics of cultural imperialism argue that the rise of a global monoculture causes a loss of local knowledge.
== Issues ==
What constitutes knowledge, certainty and [[truth]] are controversial issues. These issues are debated by [[philosopher]]s, [[social science|social scientists]], and [[history|historians]]. [[Ludwig Wittgenstein]] wrote "On Certainty" - [[aphorism]]s on these concepts - exploring relationships between knowledge and certainty. A thread of his concern has become an entire field, the [[philosophy of action]].
There are a number of problems that arise when defining knowledge or truth, including issues with objectivity, adequacy and limits to justification. Beliefs are also very problematic not least because they are either true or false, and therefore cannot be adequately described by conventional [[logic]]. An action likewise can be taken or not, but there is the troubling idea of an "event" is, an action taken by nobody, or nobody who you can blame.
== Non-scientific methods ==
Some people hold that science does not actually tell us about the physical world in which they live. They hold that the world cannot be understood by science, but rather by religious revelations, mystical experience, or literary [[deconstruction|deconstructionism]].
==Practical limits for obtaining knowledge==
What we hold to be knowledge is often derived by a combination of [[logic|reason]] from either traditional, authoritative, or [[science|scientific]] sources. Many times such knowledge is not verifiable; sometimes the process of testing is prohibitively dangerous or expensive. For instance, some physics theories about the nature of the universe, such as string-theory, require the construction of testing equipment currently beyond our technology. Since such theories are in principle subject to verification or refutation, they are scientific; since they are not proven experimentally, they are not considered certain knowledge. Rather, in such cases we have certain knowledge only of the theory, but not of what the theory describes.
''"Of the three ways in which men think that they acquire knowledge of things—authority, reasoning, and experience—only the last is effective and able to bring peace to the intellect."'' ([[Roger Bacon]], English [[alchemy|alchemist]], [[astrology|astrologer]], [[philosophy|philosopher]] and a major progenitor of modern [[science]].
==See also==
{{col-begin}}
{{col-break}}
* [[Data]]
* [[Descriptive science]]
* [[Epistemology]]
* [[Information]]
* [[Information theory]]
* [[Inquiry]]
{{col-break}}
* [[Instructional capital]]
* [[Knowledge]]
* [[Knowledge management]]
* [[Knowledge transfer]]
* [[Normative science]]
{{col-break}}
* [[Procedural knowledge]]
* [[Semiotic information theory]]
* [[Tacit knowledge]]
* [[Truth]]
* [[Understanding]]
* [[Wisdom]]
{{col-end}}
[[Category:Knowledge]]
[[Category:Semantics]]
[[de:Wissen]]
[[ja:宣言的知識]]
[[nl:Propositionele kennis]]
[[ru:Дескриптивное знание]]
[[zh:陳述性知識]]