Testimony is our primary source of social knowledge and justification. This is a primary concern of social epistemology. If perception, memory consciousness and reason were our only sources of knowledge, we wouldn’t know a whole lot. Especially children who hear a ton from the testimony of their parents. There are many types of testimony, but I’ll discuss two: formal and informal.
Formal testimony is more like the word testimony means socially today. It’s like a court room where someone recounts their first hand witnessing or an expression about the belief of something they did not witness. Informal testimony is less formal where the word testimony sounds too heavy. I went out last night isn’t exactly testimony in the formal sense, it’s simply informal.
Attesting can be a better word for the conveyance of information. It fits both formal and informal quite well.
If we think about perception it produces a non-inferential belief about what it is we perceived. Testimony produces only inferential beliefs, which means beliefs based on testimony arise by inference from one or more premises. In the case of a trial, I put the testimony into context of the trail and my own knowledge. I will only accept testimony if it seems to be true. A premise (for example) is whether the witness seems credible. If they do, I may come to believe the testimony.
If the inferentialist is correct one acquires more knowledge from perception than testimony mainly because there needs to be one or more premises that support the proposition attested (or the attester’s credibility). Also if this is true then testimony is not a direct source of knowledge or justification because one can only know or be justified only if one’s premise(s) are believed. You can’t know simply on testimony alone - only premises about it.
A different view is that is psychological. Beliefs about the credibility and beliefs associated with the attested proposition may play a filtering role. The idea here is that we don’t believe what is attested unless it “passes” the filter. Often we here things that are attested, we are fine with it, then we hear something that is like a “flag” and we don’t believe. So normally we allow content through, but once something is flagged - it’s blocked.
This idea that we let this content through at first is a kind of trust. There’s probably an evolutionary reason for this as children need to learn to reach adulthood. A child wouldn’t really be equipped to filter. Lack of filtering beliefs yields credulity. The presence of excessively rigorous one is known as skepticism.
Intellectual virtue and epistemic responsibility are attained when one can find a balance between excessive credulity and unwarranted skepticism.
Each of these accounts, inferential and non-inferential, applies to our beliefs of what we are told. At least for informal testimony beliefs, are not inferential. When speaking with a friend, one doesn’t need a premise in order to believe their content to a casual conversation.
If you take the formal view as static for how we get belief, it would be over simplifying. Let’s say you meet someone on a plane and they tell you a story about a speaker that losing their temper at a conference. At first you suspend judgment about whether this is true or not. This isn’t a common thing to happen and you don’t even know this person. As this person starts to describe more of the conference and details start falling into place, by the end of this conversation, you do believe the speaker lost their temper.
At the start, suspending judgment, may be a non-inferential response to the constraints set by my independent beliefs or sense of plausibility. The testimony is blocked by my initial beliefs/impressions. That means they prevent me from believe what is being attested, but do not lead to disbelieving it.
What is happening is as the conversation progresses, the constraints set by my independent beliefs relax and (as each new statement made) I form beliefs non-inferentially - even spontaneously. The statements no longer require the labor of my critical mind nor are they filtered out by automatic checking.
The hard part is explaining why one has a belief at the end. A good explanation is apart from forming belief about their credibility, eventually their person becomes in my eyes - credible. And now I’m disposed to believe them. This disposition grows as they speak with evident credibility and by the end this overcomes the initial resistance.
Perhaps people have a credibility scale which attesters acquire (w/o conscious attention) a place that can change (w/o conscious attention). The crucial here is seeing how beliefs grounded in testimony can be constrained by other beliefs without being inferentially based on them and how beliefs based on testimony can be formed later than the attestation that is their ultimate source.
This is similar to perception where a belief can be produced after it begins or indirectly with memory. Is this analogy good enough to conclude that testimony is a basic source of belief (ie: that it can produce belief without cooperation of another source of belief)? The problem is that you can’t form a testimony-based belief unless you hear the testimony.
A basic source does not derive its generative power from another source, but it need not operate in complete independence of another source or their outputs. It can yield belief without help of other sources, but it can also cooperate.
Perception is a requirement for the formation of belief based testimony, even if perceptual belief is not a requirement. An odd statement, but easier to understand with an example. I can be disposed to believe a speaker lost his temper to acquire a testimony based belief of the statement, but that seems to be only because I have comprehendingly perceived this being said - it does not entail I formed the belief that it was said, just belief of what it says.
Testimony can be a source of basic beliefs in the sense of beliefs not based on one or more other beliefs. This kind of non-inferential belief that testimony typically produces can also be basic knowledge if it meets the conditions for non-inferential (non-premise based) knowledge.
How does testimony yield knowledge and justification, and how does it ever yield basic knowledge or basic justification in the way perception and reflection do? Knowledge is the easier of the two to explain. Testimony gives knowledge to the hearer under certain conditions. Take the example of the conference and the speaker losing his temper, if I (the attester) don’t know anything about this conference, me attesting to it wouldn’t be knowledge. I could also be mistaken about the speaker losing their temper or I could simply be guessing and turn out to be right - by fluke - it still wouldn’t be knowledge.
Justification is different. Even if I (the attester) is not justified in believing the speaker lost his temper, I can be credible to you, in such a way that you’re justified in believing this. Consider the two facets of testimonial credibility: the sincerity dimension concerning the attester’s honesty and second competence dimension, concerning the attester’s having experience or knowledge sufficient to make it at least likely the attester holds a belief of the proposition in question or a closely related one.
Consider this: I cannot give you testimony-based knowledge that something is so without having knowledge that it is so, yet I can give you justification for believing this without having such justification. This illustrates non-transmissional grounding of justification, where testimony-based knowledge is transmissionally grounded.
A principle of testimony-based justification: normally, a belief based on testimony is thereby justified (justified on the basis of testimony) provided the believer has adequate (situational) justification for taking the tester as credible regarding the proposition in question.
Example: You ask someone for the time and they say 9am. Unless you doubt their credibility, you’re justified in believing.
Something similar can be formulated for knowledge. Undefeated testimony is when testimony occurs absent of the following:
Principle of testimony-based knowledge: a belief on undefeated testimony normally constitutes knowledge, provided the attester knows the proposition in question and the believer has no reason to doubt either the proposition or the attester’s credibility regarding it.
The dependence of testimony on other sources of belief is best demonstrated on young children. They must be told by others before they are properly justified/unjustified in believing.
There are two ways to learn from testimony: one can learn the content attested to, and one can learn something shown, but not stated, by the testimony. The first is learning that something is so. The second is learning about something.
A small child learning basic colors is not learning that the sofa is red, but becoming aware of the redness as the color of the sofa. This is learning colors and may be learning at least something about them. The proposition “the sofa is red” is propositional testimony resulting in propositional knowledge and resulting in propositional learning. When a parent is introducing vocabulary by attestation it is demonstrative testimony resulting in conceptual learning.