Western Philosophy. Группа авторов
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(or belief) is located between pure being and absolute not-being so that it amounts to neither knowledge nor complete ignorance. How does Socrates argue for this claim and what does it tell us about the objects of opinion?
Suggestions for Further Reading (Including Internet Resources)
1 Plato, Republic. Many translations are available, including F. M. Cornford (Oxford: Oxford University Press, 1941) and H. P. D. Lee (Harmondsworth: Penguin, 1955).
2 General introductions to Plato’s thought include J. C. Gosling, Plato> (London: Routledge, 1973), and A. E. Taylor, Plato: The Man and His Work (5th edn, London: Methuen, 1948).
3 For a useful guide to Plato’s Republic and in particular this topic, see G. Santas, Understanding Plato’s Republic, Ch. 7 (Oxford: Wiley-Blackwell, 2010).
4 There is an excellent account of Plato’s views on knowledge in J. Annas, An Introduction to Plato’s Republic (Oxford: Oxford University Press, 1980).
5 The nature of knowledge is discussed in many other works of Plato, especially the Theaetetus. A good starting point is F. M. Cornford, Plato’s Theory of Knowledge (London: Routledge, 1960). See also I. M. Crombie, An Examination of Plato’s Doctrines, vol. II (London: Routledge, 1963); N. P. White, Plato on Knowledge and Reality (Indianapolis: Hackett, 1976); R. Kraut (ed.), The Cambridge Companion to Plato (Cambridge: Cambridge University Press, 1991), esp. chs 6, 9.
6 In the following podcast M. M. McCabe and P. Adamson discuss Plato’s notion of knowledge: https://historyofphilosophy.net/plato-knowledge. For further related short podcasts on Plato by P. Adamson go to https://historyofphilosophy.net/plato-life.
7 For a couple of excellent online entries, see the Internet Encyclopedia of Philosophy at https://www.iep.utm.edu/republic/ (by A. Coumoundouros), and the Stanford Encyclopedia of Philosophy at https://plato.stanford.edu/entries/plato/ (by R. Kraut). See also the Stanford Encyclopedia entry ‘The Analysis of Knowledge’.
Notes
* Plato, Republic [Politeia, c.380 BC], Bk V, 474b–483e. Trans. B. Jowett, in The Dialogues of Plato (Oxford: Clarendon, 1892), vol. III, pp. 171–9.
1 1 A man who was not a man (a eunuch) threw a stone that was not a stone (a pumice stone) at a bird that was not a bird (a bat) sitting on a twig that was not a twig (a reed).
3 Demonstrative Knowledge and Its Starting Points: Aristotle, Posterior Analytics*
Readers of the preceding extracts may feel inclined to agree with Plato that knowledge is superior to mere opinion, and that it needs to go beyond the particular to some more abstract level of rational justification; but they may also feel sceptical both about the notion of innate sources of knowledge (put forward in the Meno) and also about the sharp contrast (in the Republic) between the visible and the intelligible realms, which seems to downgrade the role of ordinary sensory information as a source of knowledge. The following extract from Aristotle puts pressure on both these Platonic ideas.
In his views on knowledge, Aristotle accepted the Platonic idea that what is known must have a certain stability, and immunity from change and fluctuation. Genuine scientific knowledge, it is asserted in the following extracts from the Posterior Analytics, is of that which ‘cannot be otherwise’; it concerns ‘eternal truths’, not particulars. Aristotle also lays out a normative framework for such knowledge: it must proceed from self-evident premises, or starting points, and it must advance by rigorous logical steps from premises to conclusion. Notice that there are two requirements here. The second, that the conclusion should follow from the premises, is the requirement of deductive validity in argument (‘deductive’ because the conclusions follow inevitably from the premises from which they are logically deduced). Aristotle, in his famous theory of the syllogism, had drawn up a procedure for testing the validity of arguments (a syllogism is a standard pattern of formal valid argument, such as ‘all As are B, all Bs are C, therefore all As are C’). But validity alone does not suffice to produce knowledge. The syllogism ‘All planets are stars, all stars are square, therefore all planets are square’ is perfectly valid – the conclusion follows inescapably from the premises – but it is worthless as a contribution to scientific knowledge, since the premises, or starting points of the argument, are false. So Aristotle insists that what is required for deductive knowledge, in addition to the logical validity of the relevant argument patterns, is that the starting points themselves should be self-evidently true.
Plato, as we have seen (extract 1), believed that the mind has innate knowledge of certain self-evident truths. But Aristotle questions the suggestion that the starting points for knowledge have to be innate, stressing instead the crucial role of sense-perception in providing the raw materials of knowledge. Knowledge must involve going beyond particular instances, and grasping universal truths, but this need not, according to Aristotle, imply the existence of abstract Forms over and above particular objects and groups of objects. Rather, knowledge develops naturally from sense-perception, since the human mind has the capacity for noticing and remembering general similarities which underlie the flux of sensory experience. This faculty for grasping the universal in the particular is called by Aristotle nous or ‘intuition’ (though he does not succeed in making it clear just how the results of intuition are supposed to have the self-evidence and certainty needed to serve as the starting points for scientific demonstration).
All teaching and all intellectual learning arises from pre-existing knowledge. This is evident if we look at all the examples. For the mathematical sciences are acquired in this way, as is each of the other arts. The same goes for arguments – both syllogistic and inductive, for both produce instruction by means of what we are already aware of …
We consider we have scientific knowledge or understanding of something … when- ever we consider we know that the cause of the item in question is its cause, and that it is not possible for it to be otherwise. So it is clear that having scientific knowledge is something of this sort. For both those who do and those who do not have knowledge think that they are in this situation, the latter merely believing it, while the former are actually in it. Hence scientific knowledge relates to that which cannot be otherwise.
We shall discuss later whether there is also another way of knowing. But we can state now that there is knowledge through demonstration. By demonstration I mean a scientific syllogism, and by this I mean one whose possession constitutes scientific knowledge.
If knowledge is indeed what we have just proposed, demonstrative knowledge must necessarily depend on premises which are true, primary, immediate, and better known than, and prior to and causes of, the conclusion … Without such conditions there can be syllogisms, but not be a demonstration, since it will not produce scientific knowledge …
Since it is impossible for that of which there is knowledge to be otherwise, that which is known through demonstrative knowledge must be necessary. Demonstrative knowledge is the knowledge we have in virtue of having a demonstration. A demonstration therefore is a syllogistic deduction from necessary premises …
It is evident that if the premises of a syllogism are universal, then the conclusion of such a demonstration – demonstration in the strict sense – must also be an eternal truth. So there can be no demonstration with respect to perishable things, nor any scientific knowledge of them strictly speaking but only in the accidental sense; for in such cases the attribute does not belong to the subject universally, but only at a particular time and in some respect … Demonstrations and knowledge of things that