CHAPTER XXVIII.

THEÆTETUS.

Subjects and personages in the Theætêtus 110

Question raised by Sokrates--What is knowledge or Cognition? First answer of Theætêtus, enumerating many different cognitions. Corrected by Sokrates 111

Preliminary conversation before the second answer is given. Sokrates describes his own peculiar efficacy--mental obstetric--He cannot teach, but he can evolve knowledge out of pregnant minds 112

Ethical basis of the cross-examination of Sokrates--He is forbidden to pass by falsehood without challenge 113

Answer of Theætêtus--Cognition is sensible perception: Sokrates says that this is the same doctrine as the _Homo Mensura_ laid down by Protagoras, and that both are in close affinity with the doctrines of Homer, Herakleitus, Empedoklês, &c., all except Parmenides _ib._

Plato here blends together three distinct theories for the purpose of confuting them; yet he also professes to urge what can be said in favour of them. Difficulty of following his exposition 114

The doctrine of Protagoras is completely distinct from the other doctrines. The identification of them as one and the same is only constructive--the interpretation of Plato himself 115

Explanation of the doctrine of Protagoras--_Homo Mensura_ 116

Perpetual implication of Subject with Object--Relate and Correlate 118

Such relativity is no less true in regard to the ratiocinative combinations of each individual, than in regard to his percipient capacities _ib._

Evidence from Plato proving implication of Subject and Object, in regard to the intelligible world 121

The Protagorean measure is even more easily shown in reference to the intelligible world than in reference to sense 122

Object always relative to Subject--Either without the other, impossible. Plato admits this in Sophistes 126

Plato's representation of the Protagorean doctrine in intimate conjunction with the Herakleitean 126

Relativity of sensible facts, as described by him _ib._

Relations are nothing in the object purely and simply without a comparing subject 127

Relativity twofold--to the comparing Subject--to another object, besides the one directly described _ib._

Statement of the doctrine of Herakleitus--yet so as to implicate it with that of Protagoras 128

Agent and Patient--No absolute Ens 129

Arguments derived from dreams, fevers, &c., may be answered 130

Exposition of the Protagorean doctrine, as given here by Sokrates is to a great degree just. You cannot explain the facts of consciousness by independent Subject and Object 131

Plato's attempt to get behind the phenomena. Reference to a double potentiality--Subjective and Objective 133

Arguments advanced by the Platonic Sokrates against the Protagorean doctrine. He says that it puts the wise and foolish on a par--that it contradicts the common consciousness. Not every one, but the wise man only, is a measure 135

In matters of present sentiment every man can judge for himself. Where future consequences are involved special knowledge is required 136

Plato, when he impugns the doctrine of Protagoras, states that doctrine without the qualification properly belonging to it. All belief relative to the condition of the believing mind 137

All exposition and discussion is an assemblage of individual judgments and affirmations. This fact is disguised by elliptical forms of language 139

Argument--That the Protagorean doctrine equalises all men and animals. How far true. Not true in the sense requisite to sustain Plato's objection 141

Belief on authority is true to the believer himself--The efficacy of authority resides in the believer's own mind 142

Protagorean formula--is false, to those who dissent from it 143

Plato's argument that the wise man alone is a measure--Reply to it _ib._

Plato's argument as to the distinction between present sensation and anticipation of the future 145

The formula of Relativity does not imply that every man believes himself to be infallible _ib._

Plato's argument is untenable--That if the Protagorean formula be admitted, dialectic discussion would be annulled--The reverse is true--Dialectic recognises the autonomy of the Individual mind 146

Contrast with the Treatise De Legibus--Plato assumes infallible authority--sets aside dialectic 148

Plato in denying the Protagorean formula, constitutes himself the measure for all. Counter proposition to the formula _ib._

Import of the Protagorean formula is best seen when we state explicitly the counter-proposition 150

Unpopularity of the Protagorean formula--Most believers insist upon making themselves a measure for others, as well as for themselves. Appeal to Abstractions 150

Aristotle failed in his attempts to refute the Protagorean formula--Every reader of Aristotle will claim the right of examining for himself Aristotle's canons of truth 152

Plato's examination of the other doctrine--That knowledge is Sensible Perception. He adverts to sensible facts which are different with different Percipients 153

Such is not the case with all the facts of sense. The conditions of unanimity are best found among select facts of sense--weighing, measuring, &c. 154

Arguments of Sokrates in examining this question. Divergence between one man and another arises, not merely from different sensual impressibility, but from mental and associative difference 155

Argument--That sensible Perception does not include memory--Probability that those who held the doctrine meant to include memory 157

Argument from the analogy of seeing and not seeing at the same time _ib._

Sokrates maintains that we do not see _with_ our eyes, but that the mind sees _through_ the eyes: that the mind often conceives and judges by itself without the aid of any bodily organ 159

Indication of several judgments which the mind makes by itself--It perceives Existence, Difference, &c. 160

Sokrates maintains that knowledge is to be found, not in the Sensible Perceptions themselves, but in the comparisons add computations of the mind respecting them 161

Examination of this view--Distinction from the views of modern philosophers 162

Different views given by Plato in other dialogues 163

Plato's discussion of this question here exhibits a remarkable advance in analytical psychology. The mind rises from Sensation, first to Opinion, then to Cognition 164

Plato did not recognise Verification from experience, or from facts of sense, as either necessary or possible 168

Second definition given by Theætêtus--That Cognition consists in right or true opinion _ib._

Objection by Sokrates--This definition assumes that there are false opinions. But how can false opinions be possible? How can we conceive Non-Ens: or confound together two distinct realities? _ib._

Waxen memorial tablet in the mind, on which past impressions are engraved. False opinion consists in wrongly identifying present sensations with past impressions 169

Sokrates refutes this assumption. Dilemma. Either false opinion is impossible, or else a man may know what he does not know 170

He draws distinction between possessing knowledge, and having it actually in hand. Simile of the pigeon-cage with caught pigeons turned into it and flying about _ib._

Sokrates refutes this. Suggestion of Theætêtus--That there may be non-cognitions in the mind as well as cognitions, and that false opinion may consist in confounding one with the other. Sokrates rejects this 171

He brings another argument to prove that Cognition is not the same as true opinion. Rhetors persuade or communicate true opinion; but they do not teach or communicate knowledge 172

New answer of Theætêtus--Cognition is true opinion, coupled with rational explanation 173

Criticism on the answer by Sokrates. Analogy of letters and words, primordial elements and compounds. Elements cannot be explained: compounds alone can be explained _ib._

Sokrates refutes this criticism. If the elements are unknowable, the compound must be unknowable also 174

Rational explanation may have one of three different meanings. 1. Description in appropriate language. 2. Enumeration of all the component elements in the compound. In neither of these meanings will the definition of Cognition hold _ib._

Third meaning. To assign some mark, whereby the thing to be explained differs from everything else. The definition will not hold. For rational explanation, in this sense, is already included in true opinion 175

Conclusion of the dialogue--Summing up by Sokrates--Value of the result, although purely negative 176

Remarks on the dialogue. View of Plato. False persuasion of knowledge removed. Importance of such removal _ib._

Formation of the testing or verifying power in men's minds, value of the Theætêtus, as it exhibits Sokrates demolishing his own suggestions 177

Comparison of the Philosopher with the Rhetor. The Rhetor is enslaved to the opinions of auditors 178

The Philosopher is master of his own debates 179

Purpose of dialogue to qualify for a life of philosophical Search _ib._

Difficulties of the Theætêtus are not solved in any other Dialogue 180

Plato considered that the search for Truth was the noblest occupation of life 182

Contrast between the philosopher and the practical statesman--between Knowledge and Opinion 183