- Why is there more to knowledge than merely true belief, or even justified true belief?
- What is the structure of knowledge? More specifically, must knowledge be grounded in epistemic foundations?
- What is the relationship between knowledge and rationality?
- Why, if at all, is knowledge valuable?
The study of knowledge, ‘epistemology’, is an important philosophical field. I will address two questions: ‘what is knowledge?’ and ‘what is the value of knowledge?’.
Three different types of knowledge can be identified. Firstly, the knowledge of how to do something (for example, I know how to tie a shoelace), this is called ‘ability’ knowledge. Secondly, we can have knowledge of people or places (for example, ‘I know Mr Smith’), this is referred to as ‘acquaintance’ knowledge. Thirdly, the kind that is of most relevance to philosophy, ‘propositional knowledge’ is the knowledge that something is the case (for example, it is the case that the Earth orbits the Sun).
What is the value of knowledge? Knowledge frequently has instrumental value in that it helps us to achieve an objective. For example, the knowledge of a street layout can help to plan the shortest route home. There is no settled philosophical consensus as to whether knowledge has intrinsic value, i.e. is valuable in itself. I regard intrinsic value as being dependant on a person’s value-system. It seems possible to attribute value to different virtues and it is therefore possible to regard knowledge (or wisdom) as virtuous. A more utilitarian view would reject this analysis and argue that value is only ultimately attributable to happiness; knowledge is instrumentally valuable if it contributes towards general happiness and has no intrinsic value.
Two philosophical approaches can be identified for investigating the problem of knowledge. Particularism asks what are the common features of all cases of knowledge. Methodism looks at the sources of knowledge and the methods by which it is obtained. Both approaches assume that we have knowledge in the first place and suffer from the problem of the criterion, whereby in order to take a particularist approach we presume we know the method to use and vice versa. The problem of the criterion has led some to tend towards scepticism.
A traditional definition of knowledge posits that three conditions are necessary for a subject to be regarded as knowing a meaningful proposition. Firstly, it is un-contentious that the proposition must be true and not false. We cannot ‘know’ something that is false, for example that the Sun orbits the Earth. Secondly, it is also generally un-contentious that the subject must believe that the proposition is true. Thirdly, it is often claimed that the subject must be justified in their true belief in the proposition. When combined together these three (‘JTB’) conditions may be regarded as necessary and sufficient for a definition of knowledge.
Edmund Gettier pointed out a potential shortcoming to the JTB definition by providing example cases in which the subject has justified true belief which has been obtained by luck, which do not count as knowledge. The most persuasive objection to Gettier’s cases is that the subject is not in fact justified in their belief in the examples given. If we accept that JTB is not sufficient, additional conditions can be formulated such as the absence of ‘knowledge defeaters’, also known as the defeasibility condition.
There are three key theories of justification for propositional knowledge, foundationalism, infinitism and coherentism. Agrippa’s trilemma points out that none seem to be entirely satisfactory. I suspect that we deploy all three sources of justification to different degrees in different circumstances.
Justification criteria have led to much philosophical discussion. It is widely accepted that to be epistemologically justified in holding a belief, the subject must have acquired the belief through a rational process. There is much debate as to how to define what makes a process ‘rational’, whether it depends only subjectively on the (responsible) process that has been followed (deontic epistemic rationality) or if it depends on compliance with epistemic norms which are objectively appropriate (non-deontic/ externalist rationality). My view is that non-deontic rationality more closely matches the process of acquiring propositional knowledge.