19 Facts About Speusippus

1.

Speusippus rejected Plato's Theory of Forms, and whereas Plato had identified the Good with the ultimate principle, Speusippus maintained that the Good was merely secondary.

2.

Speusippus argued that it is impossible to have satisfactory knowledge of any thing without knowing all the differences by which it is separated from everything else.

3.

Speusippus was a native of Athens, and the son of Eurymedon and Potone, a sister of Plato, he belonged to the deme of Myrrhinus.

4.

The pseudonymous Thirteenth Letter of Plato claims that Speusippus married his niece.

5.

Speusippus died, it appears, of a lingering paralytic illness, presumably a stroke.

6.

Speusippus was succeeded as the head of the school by Xenocrates.

7.

Diogenes Laertius gives us a list of some of the titles of the many dialogues and commentaries of Speusippus, which is of little help in determining their contents, and the fragments provided by other writers provide us with only a little extra.

8.

Speusippus was interested in bringing together those things which were similar in their philosophical treatment, and in the derivation, and laying down, of the ideas of genera and species: for he was interested in what the various sciences had in common, and how they might be connected.

9.

Speusippus maintained that no one could arrive at a complete definition who did not know all the differences by which a thing which was to be defined was separated from the rest.

10.

Speusippus tried to show how perception can be taken up and transformed into knowledge, by the assumption of a perception, which, by participation in rational truth, raises itself to the rank of knowledge.

11.

Speusippus tried to determine the idea of substance more distinctly by separating its types, the difference between which he considered would result from the difference between the principles on which they are based.

12.

Speusippus made still more kinds of substance, beginning with the One, and assuming principles for each kind of substance, one for numbers, another for spatial magnitudes, and then another for the soul; and by going on in this way he multiplies the kinds of substance.

13.

Nevertheless, Speusippus must have recognised something common in those different kinds of substances, inasmuch as, firstly, he set out from the absolute One, and regarded it as a formal principle which they had in common, and, secondly, he appears to have assumed that multitude and multiformity was a common primary element in their composition.

14.

Speusippus [supposes] that supreme beauty and goodness are not present in the beginning, because the beginnings both of plants and of animals are causes, but beauty and completeness are in the effects of these.

15.

Nevertheless, Speusippus seems to have attributed vital activity to the primordial Unity, as inseparably belonging to it, probably in order to explain how it could grow, by a process of self-development, into the good, spirit, etc.

16.

Less worthy of notice is the attempt by Speusippus to find a more suitable expression for the material principle, the indefinite duality of Plato; and his Pythagorizing mode of treating the doctrine of numbers which we can see in the extracts of his treatise on the Pythagorean numbers.

17.

Diogenes Laertius' list of Speusippus' works includes titles on justice, friendship, pleasure, and wealth.

18.

Eudoxus accepts that the Good will be that at which all people aim, but identifies this as pleasure, as opposed to Speusippus' exclusive focus on moral goods.

19.

Speusippus seems to have developed further Plato's ideas of justice and of the citizen, and the fundamental principles of legislation.