Two points are here to be noted, as contained and debated in the handling of this dialogue. 1. Knowledge absolutely, is a word without meaning: all knowledge is relative, and has a definite object or _cognitum_: there can be no _scientia scientiarum_. 2. Among the various objects of knowledge (_cognita_ or _cognoscenda_), one is, _good and evil_. There is a science of good and evil, the function of which is, to watch over and compare the results of the other sciences, in order to promote results of happiness, and to prevent results of misery: without the supervision of this latter science, the other sciences might be all exactly followed out, but no rational comparison could be had between them.[44] In other words, there is a science of Ends, estimating the comparative worth of each End in relation to other Ends (Teleology): distinct from those other more special sciences, which study the means each towards a separate End of its own. Here we fall into the same track as we have already indicated in Lachês and Alkibiadês II. [Footnote 44: Compare what has been said upon the same subject in my remarks on Alkib. i. and ii. p. 31.**] [Side-note: Courage and Temperance, handled both by Plato and by Aristotle. Comparison between the two.] These matters I shall revert to in other dialogues, where we shall find them turned over and canvassed in many different ways. One farther observation remains to be made on the Lachês and Charmidês, discussing as they do Courage (which is also again discussed in the Protagoras) and Temperance. An interesting comparison may be made between them and the third book of the Nikomachean Ethics of Aristotle,[45] where the same two subjects are handled in the Aristotelian manner. The direct, didactic, systematising, brevity of Aristotle contrasts remarkably with the indirect and circuitous prolixity, the multiplied suggestive comparisons, the shifting points of view, which we find in Plato. Each has its advantages: and both together will be found not more than sufficient, for any one who is seriously bent on acquiring what Plato calls knowledge, with the cross-examining power included in it. Aristotle is greatly superior to Plato in one important attribute of a philosopher: in the care which he takes to discriminate the different significations of the same word: the univocal and the equivocal, the generically identical from the remotely analogical, the proper from the improper, the literal from the metaphorical. Of such precautions we discover little or no trace in Plato, who sometimes seems not merely to neglect, but even to deride them. Yet Aristotle, assisted as he was by all Plato's speculations before us, is not to be understood as having superseded the necessity for that negative Elenchus which animates the Platonic dialogues of Search: nor would his affirmative doctrines have held their grounds before a cross-examining Sokrates.