Certainty (SEP)
Certainty, or the attempt to obtain certainty, has played a central role in the history of philosophy. Some philosophers have taken the kind of certainty characteristic of mathematical knowledge to be the goal at which philosophy should aim. In the Republic, Plato says that geometry “draws the soul towards truth and produces philosophic thought by directing upwards what we now wrongly direct downwards” (527b). Descartes also thought that a philosophical method that proceeds in a mathematical way, enumerating and ordering everything exactly, “contains everything that gives certainty to the rules of mathematics” (Discourse on the Method, PW 1, p. 121). Other philosophers have adopted different models for how to best understand certainty. For example, Aristotle and Aquinas take scientific explanation to be essential to certainty (see Pasnau 2017, pp. 5–7), while Al-Ghazālī thought that certainty arose out of religious practice (see Albertini 2005). For many empiricists, certainty with respect to empirical matters is to be found in basic beliefs that are grounded in some fundamental aspect of perceptual experience (see, e.g., Lewis 1952).
Like knowledge, certainty is an epistemic property of beliefs. (In a derivative way, certainty is also an epistemic property of subjects: S is certain that p just in case S’s belief that p is certain.) Although some philosophers have thought that there is no difference between knowledge and certainty, it has become increasingly common to distinguish them. On this conception, then, certainty is either the highest form of knowledge or is the only epistemic property superior to knowledge. One of the primary motivations for allowing kinds of knowledge less than certainty is the widespread sense that skeptical arguments are successful in showing that we rarely or never have beliefs that are certain (see Unger 1975 for this kind of skeptical argument) but do not succeed in showing that our beliefs are altogether without epistemic worth (see, for example, Lehrer 1974, Williams 1999, and Feldman 2003; see Fumerton 1995 for an argument that skepticism undermines every epistemic status a belief might have; and see Klein 1981 for the argument that knowledge requires certainty, which we are capable of having).
As with knowledge, it is difficult to provide an uncontentious analysis of certainty. There are several reasons for this. One is that there are different kinds of certainty, which are easy to conflate. Another is that the full value of certainty is surprisingly hard to capture. A third reason is that there are two dimensions to certainty: a belief can be individually certain at a particular moment, or it can be certain over some greater length of time in a system of beliefs.
Read the rest here: https://plato.stanford.edu/entries/certainty/
Chatbot
Certainty is the state of being completely convinced that a proposition is true, leaving no doubt. In philosophy it refers to the strongest possible epistemic justification for a belief.
A distinction is usually made between psychological certainty and epistemic certainty. Psychological certainty means a person feels no doubt. This is a mental state and can be mistaken; people can be completely convinced of false things. Epistemic certainty refers to whether a belief is justified in such a way that error is impossible or extremely unlikely.
Philosophers have disagreed about whether true certainty is achievable.
Descartes argued that certainty exists in a limited form. Through methodological doubt he tried to doubt everything that could possibly be false. The one thing he believed survived this process was the cogito: “I think, therefore I am.” The act of doubting proves the existence of the doubter.
Empiricists such as Hume were more skeptical. They argued that most of what we believe about the world is based on habit and probability rather than certainty. For example, we believe the sun will rise tomorrow, but this is not logically certain.
In modern epistemology, many philosophers accept that most knowledge is fallible. Instead of certainty, they focus on degrees of justification or probability. Scientific knowledge, for example, is generally treated as highly supported but always revisable.
In short: certainty is the ideal of indubitable knowledge, but whether humans can actually achieve it—outside of logic or mathematics—is widely disputed.
Wikipedia
Certainty (also known as epistemic certainty or objective certainty) is the epistemic property of beliefs which a person has no rational grounds for doubting. One standard way of defining epistemic certainty is that a belief is certain if and only if the person holding that belief could not be mistaken in holding that belief. Other common definitions of certainty involve the indubitable nature of such beliefs or define certainty as a property of those beliefs with the greatest possible justification. Certainty is closely related to knowledge, although contemporary philosophers tend to treat knowledge as having lower requirements than certainty.
Importantly, epistemic certainty is not the same thing as psychological certainty (also known as subjective certainty or certitude), which describes the highest degree to which a person could be convinced that something is true. While a person may be completely convinced that a particular belief is true, and might even be psychologically incapable of entertaining its falsity, this does not entail that the belief is itself beyond rational doubt or incapable of being false. While the word “certainty” is sometimes used to refer to a person’s subjective certainty about the truth of a belief, philosophers are primarily interested in the question of whether any beliefs ever attain objective certainty.
The philosophical question of whether one can ever be truly certain about anything has been widely debated for centuries. Many proponents of philosophical skepticism deny that certainty is possible, or claim that it is only possible in a priori domains such as logic or mathematics. Historically, many philosophers have held that knowledge requires epistemic certainty, and therefore that one must have infallible justification in order to count as knowing the truth of a proposition. However, many philosophers such as René Descartes were troubled by the resulting skeptical implications, since all of our experiences at least seem to be compatible with various skeptical scenarios. It is generally accepted today that most of our beliefs are compatible with their falsity and are therefore fallible, although the status of being certain is still often ascribed to a limited range of beliefs (such as “I exist”). The apparent fallibility of our beliefs has led many contemporary philosophers to deny that knowledge requires certainty.
Nochrisis 