But I am sure that the dialectic power is something of the nature which I have described. It is the only force which can make plain the full truth to students who have gone through the preliminary studies that we have described. It is the only study which investigates rationally real forms and essences[243]--what each thing is, truly in itself. Other branches of study are directed either towards the opinions and preferences of men--or towards generation and combination of particular results--or towards upholding of combinations already produced or naturally springing up: while even as to geometry and the other kindred studies, we have seen that as to real essence, they have nothing better than dreams[244]--and that they cannot see it as it is, so long as they take for their principle or point of departure certain assumptions or hypotheses of which they can render no account. The principle being thus unknown, and the conclusion as well as the intermediate items being spun together out of that unknown, how can such a convention deserve the name of Science?[245] Pursuant to custom, indeed, we call these by the name of Sciences. But they deserve no higher title than that of Intellectual Cognitions, lower than Science, yet higher than mere Opinion. It is the Dialectician alone who discards all assumptions, ascending at once to real essence as his principle and point of departure:[246] defining, and discriminating by appropriate words, each variety of real essence--rendering account of it to others--and carrying it safely through the cross-examining process of question and answer.[247] Whoever cannot discriminate in this way the Idea or Form of Good from every thing else, will have no proper cognition of Good itself, but only, at best, opinions respecting the various shadows of Good. Dialectic--the capacity of discriminating real Forms and maintaining them in cross-examining dialogue is thus the coping-stone, completion, or consummation, of all the other sciences.[248] [Footnote 243: Plato, Republic, vii. p. 533 B. [Greek: ô(s au)tou= ge e(ka/stou pe/ri, o(\ e)/stin e(/kaston, ou)k a)/llê tis e)picheirei= me/thodos o(dô=| peri\ panto\s lamba/nein], &c.] [Footnote 244: Plato, Republic, vii. p. 533 C. [Greek: ô(s o)neirô/ttousi me\n peri\ to\ o)/n, u(/par de\ a)du/naton au)tai=s i)dei=n, e(/ôs a)\n u(pothe/sesi chrô/menai tau/tas a)kinê/tous e)ô=sin], &c.] [Footnote 245: Plato, Republic, vii. p. 533 D.] [Footnote 246: Plato, Republic, vii. p. 533 E.] [Footnote 247: Plato, Republic, vii. p. 534 B. [Greek: ê)= kai\ dialektiko\n kalei=s to\n lo/gon e(/kastou lamba/nonta tê=s ou)si/as?]] [Footnote 248: Plato, Republic, vii. p. 534 C-E. [Greek: ô(/sper thrigko\s toi=s mathê/masin ê( dialektikê\ ê(mi=n e)pa/nô kei=sthai], &c.] [Side-note: The Synoptic view peculiar to the Dialectician.] [Side-note: Scale and duration of various studies for the Guardians, from youth upwards.]