Knowledge by acquaintance
Encyclopedia
The contrasting expressions "knowledge by acquaintance" and "knowledge by description
" were promoted by Bertrand Russell
, who was extremely critical of the equivocal nature of the word know, and believed that the equivocation arose from a failure to distinguish between the two fundamentally different types of knowledge.
distinguished between what he described as "knowledge of acquaintance" and "knowledge-about". Grote noted that these distinctions were made in many languages. He cited Greek (γνωναι and ειδεναι), Latin (noscere and scire), German (kennen and wissen), and French (connaître and savoir) as examples.
Grote’s "knowledge of acquaintance" is far better known today as "knowledge by acquaintance" following Russell’s decision to change the preposition in a paper that he read to the Aristotelian Society
on 6 March 1911.
clearly distinguished between das Kennen, the knowledge that consisted of "mere familiarity with phenomena", and das Wissen, "the knowledge of [phenomena] which can be communicated by speech". Stressing that the Kennen sort of knowledge could not "compete with" the Wissen sort of knowledge, Helmholtz argued that, despite the fact that it might be of "the highest possible degree of precision and certainty", the Kennen kind of knowledge can not be expressed in words, "even to ourselves".
, agreeing there were two fundamental kinds of knowledge, and adopting Grote's terminology, further developed the distinctions made by Grote and Helmholtz:
) and his thoughts and ideas. However, other people could not become acquainted with another person's mind, for example. They have no way of directly interacting with it, since a mind is an internal object. They can only perceive that a mind could exist by observing that person's behaviour.
To be fully justified in believing a proposition to be true one must be acquainted, not only with the fact that supposedly makes the proposition true, but with the relation of correspondence that holds between the proposition and the fact. In other words, justified true belief can only occur if I know that a proposition (e.g. "Snow is white") is true in virtue of a fact (e.g. that the frequency of the light reflected off the snow causes the human eye, and by extension, the human mind, to perceive snow to be white). By way of example, John is justified in believing that he is in pain if he is directly and immediately acquainted with his pain. Not if John makes an inference regarding his pain ("I must be in pain because my arm is bleeding"), but feels it as an immediate sensation ("My arm hurts!").
This direct contact with the fact and the knowledge that this fact makes a proposition true is what is meant with knowledge by acquaintance.
On the contrary, when one is not directly and immediately acquainted with a fact, such as Julius Caesar
's assassination, we speak of knowledge by description. When one is not directly in contact with the fact, but knows it only indirectly by means of a description, one arguably is not entirely justified in holding a proposition true (such as e.g. "Caesar was killed by Brutus").
The acquaintance theorist can argue that one has noninferentially justified belief "that P" only when one has the thought "that P" and one is acquainted with both the fact that P is the case, the thought "that P", and the relation of correspondence holding between the thought "that P" and the fact that P is the case. So I must not only know the proposition P, and the fact that P is the case, but also know that the fact that P is the case is what makes proposition P true.
Knowledge by description
The contrasting expressions "knowledge by description" and "knowledge by acquaintance" were promoted by Bertrand Russell, who was extremely critical of the equivocal nature of the word know, and believed that the equivocation arose from a failure to distinguish between the two fundamentally...
" were promoted by Bertrand Russell
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS was a British philosopher, logician, mathematician, historian, and social critic. At various points in his life he considered himself a liberal, a socialist, and a pacifist, but he also admitted that he had never been any of these things...
, who was extremely critical of the equivocal nature of the word know, and believed that the equivocation arose from a failure to distinguish between the two fundamentally different types of knowledge.
Grote
In 1865, philosopher John GroteJohn Grote
John Grote was an English moral philosopher and Anglican clergyman.The son of a banker, Grote was younger brother to the historian, philosopher and reformer George Grote...
distinguished between what he described as "knowledge of acquaintance" and "knowledge-about". Grote noted that these distinctions were made in many languages. He cited Greek (γνωναι and ειδεναι), Latin (noscere and scire), German (kennen and wissen), and French (connaître and savoir) as examples.
Grote’s "knowledge of acquaintance" is far better known today as "knowledge by acquaintance" following Russell’s decision to change the preposition in a paper that he read to the Aristotelian Society
Aristotelian Society
The Aristotelian Society for the Systematic Study of Philosophy was founded at a meeting on 19 April 1880, at 17 Bloomsbury Square which resolved "to constitute a society of about twenty and to include ladies; the society to meet fortnightly, on Mondays at 8 o'clock, at the rooms of the Spelling...
on 6 March 1911.
Helmholtz
In a similar fashion, in 1868 Hermann von HelmholtzHermann von Helmholtz
Hermann Ludwig Ferdinand von Helmholtz was a German physician and physicist who made significant contributions to several widely varied areas of modern science...
clearly distinguished between das Kennen, the knowledge that consisted of "mere familiarity with phenomena", and das Wissen, "the knowledge of [phenomena] which can be communicated by speech". Stressing that the Kennen sort of knowledge could not "compete with" the Wissen sort of knowledge, Helmholtz argued that, despite the fact that it might be of "the highest possible degree of precision and certainty", the Kennen kind of knowledge can not be expressed in words, "even to ourselves".
James
In 1890, William JamesWilliam James
William James was a pioneering American psychologist and philosopher who was trained as a physician. He wrote influential books on the young science of psychology, educational psychology, psychology of religious experience and mysticism, and on the philosophy of pragmatism...
, agreeing there were two fundamental kinds of knowledge, and adopting Grote's terminology, further developed the distinctions made by Grote and Helmholtz:
- I am acquainted with many people and things, which I know very little about, except their presence in the places where I have met them. I know the color blue when I see it, and the flavor of a pear when I taste it; I know an inch when I move my finger through it; a second of time, when I feel it pass; an effort of attention when I make it; a difference between two things when I notice it; but about the inner nature of these facts or what makes them what they are, I can say nothing at all. I cannot impart acquaintance with them to any one who has not already made it himself I cannot describe them, make a blind man guess what blue is like, define to a child a syllogism, or tell a philosopher in just what respect distance is just what it is, and differs from other forms of relation. At most, I can say to my friends, Go to certain places and act in certain ways, and these objects will probably come. (1890, p.221)
Russell
According to Russell, knowledge by acquaintance is obtained through a direct causal (experience-based) interaction between a person and the object that person is perceiving. Sense-data from that object are the only things that people can ever become acquainted with; they can never truly KNOW the physical object itself. A person can also be acquainted with his own sense of self (cogito ergo sumCogito ergo sum
is a philosophical Latin statement proposed by . The simple meaning of the phrase is that someone wondering whether or not they exist is, in and of itself, proof that something, an "I", exists to do the thinking — However this "I" is not the more or less permanent person we call "I"...
) and his thoughts and ideas. However, other people could not become acquainted with another person's mind, for example. They have no way of directly interacting with it, since a mind is an internal object. They can only perceive that a mind could exist by observing that person's behaviour.
To be fully justified in believing a proposition to be true one must be acquainted, not only with the fact that supposedly makes the proposition true, but with the relation of correspondence that holds between the proposition and the fact. In other words, justified true belief can only occur if I know that a proposition (e.g. "Snow is white") is true in virtue of a fact (e.g. that the frequency of the light reflected off the snow causes the human eye, and by extension, the human mind, to perceive snow to be white). By way of example, John is justified in believing that he is in pain if he is directly and immediately acquainted with his pain. Not if John makes an inference regarding his pain ("I must be in pain because my arm is bleeding"), but feels it as an immediate sensation ("My arm hurts!").
This direct contact with the fact and the knowledge that this fact makes a proposition true is what is meant with knowledge by acquaintance.
On the contrary, when one is not directly and immediately acquainted with a fact, such as Julius Caesar
Julius Caesar
Gaius Julius Caesar was a Roman general and statesman and a distinguished writer of Latin prose. He played a critical role in the gradual transformation of the Roman Republic into the Roman Empire....
's assassination, we speak of knowledge by description. When one is not directly in contact with the fact, but knows it only indirectly by means of a description, one arguably is not entirely justified in holding a proposition true (such as e.g. "Caesar was killed by Brutus").
The acquaintance theorist can argue that one has noninferentially justified belief "that P" only when one has the thought "that P" and one is acquainted with both the fact that P is the case, the thought "that P", and the relation of correspondence holding between the thought "that P" and the fact that P is the case. So I must not only know the proposition P, and the fact that P is the case, but also know that the fact that P is the case is what makes proposition P true.
External links
- Knowledge by Acquaintance vs. Description. Entry from the Stanford Encyclopedia of PhilosophyStanford Encyclopedia of PhilosophyThe Stanford Encyclopedia of Philosophy is a freely-accessible online encyclopedia of philosophy maintained by Stanford University. Each entry is written and maintained by an expert in the field, including professors from over 65 academic institutions worldwide...
.