Diogenes Laertius offers a very brief overview of Potamo's doctrines, based on the traditional division of philosophy into logic (where epistemology played a central role), physics and ethics (compare D.L. 7.39–41, with reference to the Stoics). Within this scheme, the short report concentrates on Potamo's responses to the central issues on which one needed to articulate a position in order to declare allegiance to a particular school or venture a claim of doctrinal originality: the criterion of truth (epistemology); the first principles (physics); and the moral end (ethics). The few lines from Diogenes have to provide the bulk of our evidence for an assessment of Potamo's eclecticism and the type of approach to preceding philosophical traditions that this (self-) characterisation implies.

Recalling the programmatic report that Potamo ‘selected the doctrines (i.e. his doctrines) from each of the sects’, important questions that will come under consideration include (i) Which sects are understood in the rather vague expression ‘each of the sects’? (ii) Does Potamo select ideas from each of these equally, or is he influenced by some more than by others? (iii) Should we imagine his Stoicheiosis as an anthology of ‘approved’ (ἀρέσαντα) doctrines simply listed side by side, or as an attempt to make something out of the selected ideas by drawing connections and correlations? The information that Potamo was not simply a historian of philosophy but had introduced his own sect, which would require a programmatically distinct intellectual attitude of some sort, already points towards the latter option.

The Background

The capital of the Ptolemaic kingdom was the undisputed centre of intellectual life in the Hellenistic period. It benefited from active royal patronage that went beyond favouring gifted individuals in court, to include the establishment of permanent institutions devoted to learning and research. The achievements of scientists and literary scholars associated with the Museum and Library of Alexandria remained extremely influential for a long time after its heyday in the third century bc. There is therefore a striking contrast with the field of philosophy, where Ptolemaic Alexandria does not have anything as remarkable to offer.

There are two references to Potamo in Simplicius’ commentary on Aristotle's On the Heavens. Both come from his comments on the third book of the work, which contains Aristotle's discussion of the earthly elements, their number and properties, and is dominated by a critique of earlier theories. The first reference to Potamo is part of Simplicius’ discussion of Aristotle's views on the number of elements. Aristotle introduces the topic as follows: πότερον δὲ πεπερασμένα ἢ ἄπειρα, καὶ εἰ πεπερασμένα, πόσα τὸν ἀριθμόν, ἑπόμενον ἂν εἴη σκοπεῖν (‘the next thing would be to examine whether they are limited or infinite, and if they are limited, how many in number’, Cael. 3.4.302b10–11). More specifically, Potamo's intervention is related to the criticism of the view Aristotle ascribes to Anaxagoras, namely that there is an infinite number of entities, divisible into parts that are the same as each other and the whole (ὁμοιομερῆ), which Aristotle treats as equivalent to his elements. He argues that even on Anaxagoras’ view one need not postulate an infinite number:

Eclecticism is not often thought of as representing something new, something that ‘emerges’ as a fresh beginning – the term is used more commonly for intellectual attitudes that are viewed as the end or the anticlimax after a period of development and innovation. This book proposes to examine the circumstances under which an unexpected claim of innovation was made on behalf of eclecticism. Potamo of Alexandria was the only ancient philosopher explicitly to declare himself an eclectic, and what is more, he went on to establish a new philosophical sect under the banner of eclecticism. As discussed in more detail in alongside a survey of ancient and modern applications of the term ‘eclectic’, in ancient philosophy eclecticism has served primarily as a conventional characterisation for many different thinkers such as Cicero, Antiochus of Ascalon, Eudorus of Alexandria or Plutarch, whose views cannot be pinned down firmly to one of the traditional schools (such as the Academy, the Peripatos, the Stoa or Epicurus’ Garden). Many of the problems arising from this characterisation were treated in the volume The Question of Eclecticism, where chapters are devoted to Cicero, Philo of Alexandria and Plutarch among others. The main common feature among ‘eclectic’ or Eclectic philosophers remains the elusive nature of their otherwise diverse ideas. What radically distinguishes the other thinkers from Potamo is that they, formally at least, claimed allegiance to one of the traditional schools.