His de rebus Caesar certior factus et infirmitatem Gallorum veritus, quod sunt in consiliis capiendis mobiles et novis plerumque rebus student, nihil his committendum existimavit. Est enim hoc Gallicae consuetudinis, uti et viatores etiam invitos consistere cogant et quod quisque eorum de quaque re audierit aut cognoverit quaerant, et mercatores in oppidis vulgus circumsistat, quibusque ex regionibus veniant quasque ibi res cognoverint pronuntiare cogant. His rebus atque auditionibus permoti de summis saepe rebus consilia ineunt quorum eos in vestigio paenitere necesse est, cum incertis rumoribus serviant et plerique ad voluntatem eorum ficta respondeant.
The OCT divides the section into three subsections, as follows:
His de rebus Caesar certior factus et infirmitatem Gallorum veritus, quod sunt in consiliis capiendis mobiles et novis plerumque rebus student, nihil his committendum existimavit.
Est enim hoc Gallicae consuetudinis, uti et viatores etiam invitos consistere cogant et quod quisque eorum de quaque re audierit aut cognoverit quaerant, et mercatores in oppidis vulgus circumsistat, quibusque ex regionibus veniant quasque ibi res cognoverint pronuntiare cogant.
His rebus atque auditionibus permoti de summis saepe rebus consilia ineunt quorum eos in vestigio paenitere necesse est, cum incertis rumoribus serviant et plerique ad voluntatem eorum ficta respondeant.
And these subsections are themselves micro-analyzable into the following structure:
[NB numbering in first column to the left follows the OCT text, the second column is my numbering strictly for purposes of reference in the subsequent discussion, and the third column begins the first degree of subordination — each additional indentation thereafter marks one further degree of subordination.]
1 His de rebus Caesar certior factus
3 infirmitatem Gallorum veritus
5 sunt in consiliis capiendis mobiles
7 novis plerumque rebus student,
9 his committendum
11 Est enim hoc Gallicae consuetudinis
13 et viatores etiam invitos consistere cogant
15 quod quisque eorum de quaque re
20 et mercatores in oppidis vulgus circumsistat
21 quibusque ex regionibus veniant
22 quasque ibi res cognoverint
23 pronuntiare cogant.
24 His rebus atque auditionibus permoti
25 de summis saepe rebus consilia ineunt
26 quorum eos in vestigio paenitere necesse est
27 cum incertis rumoribus serviant
29 plerique ad voluntatem eorum ficta respondeant.
[At this point it would be a good idea to copy this structure and print it out. The following discussion will be a lot easier — difficult enough as it already is — to follow if you have the passage thus analyzed in front of you.]
Once we have unpacked the density of the Latin, it becomes clear that Caesar is here denigrating the Gauls much as he had Orgetorix and his Helvetii co-conspirators earlier at 1.2, for now he points out how vastly superior the Romans are to the childlike Gauls and underscores the point through his typically masterful control of the Latin. The significant markers that point to the incisive contrast are the two phrases His de rebus (1) and His rebus (24). If we follow through on this initial echo, we see quite clearly how antithetical the customary practices of Caesar and the Gauls (Gallicae consuetudinis ) truly are.
Caesar makes sure to get adequate information (his de rebus … certior factus ) about what is going on; he knows the Gauls are fickle as well as eager revolutionaries, and, thus informed, elects to do nothing (8-10). The Gauls on the other hand are emotionally worked up (His rebus … permoti ) and plunge straight into deliberations about highly important matters. It is the classic face-off between calculated reason on the one hand and fickle emotion on the other, a kind of establishing ‘shot’ (if we were to think about the passage in cinematic terms) of a fundamental and differentiating polarity entailing diametrically opposed sensibilities.
This polarity is underscored by the observation that the Gauls rush to action on the basis of rumors and hearsay (auditionibus  … incertis rumoribus ), and they uncritically believe the self-serving stories (ficta ) of coerced (cogant … cogant [13 … 23]) strangers (viatores  … mercatores ) about what the Romans are up to. Caesar’s large and complex tetradic (et … cogant  … et … quaerant [14 … 19] … et … circumsitat  … –que … cogant [21 … 23]) architecture (13 … 23) detailing their standard operating procedures (consuetudinis ), in iconic fashion offers a highly ironic commentary on the uselessness of massive but unreliable and unverifiable information in making military plans. Contrast the cool and succinct brevity of Caesar’s operation by comparison with that of the Gauls: nihil his committendum existimavit (8-10). Further, one might well take notice of the unifying homoioteleuta in the section: cogant (13) … quaerant (19) … cogant (23) – of the four cola the third is singular (circumsistat ) and by its divergence from pattern perhaps calls attention to a unifying function inherent in the use of homoiteleuton (see more on this point below). Note too veniant (21) which, although not syntactically parallel (it is a subordinate verb within the final of the four cola in the tetrad) to cogant (13) … quaerant (19) … cogant (23) … circumsistat (24), nevertheless has a desinence in –ant and thus echoes the other ‘-ant verbs’.
Additional ‘cement’ giving cohesion to the characterization of the Gauls is such features as the echoes in viatores (13) / mercatores (20), in audierit (16) / cognoverit (18), quibusque (21) / quasque (22). Although –que … –que provide a phonic echo, syntactically they are not parallel: the first –que (in quibusque ) is (again, a pattern-divergent) part of the et (13) … et (14) … et (20) organization, and the second –que (in quasque ) merely couples the two clauses quibus… ex regionibus veniant (21) and quas… ibi res cognoverint (22), this cognoverint picking up earlier cognoverit (18).
The indicatives sunt (5) and student (7) in the causal quod-clause (4-7) launched by veritus (3) call attention to the factual certainty on Caesar’s part of the information that forms the basis for his decisions. The Gauls, by contrast, are entirely credulous of hearsay information – information offered under compulsion at that.
Now that you understand how the sentence is put together, you can appreciate the flavor that structural parallelism imparts to that (see above) fairly neutral circumsistat (20): in league with cogant (13), querant (19), and, again – nothing like waving a red flag! — cogant (23), it more than merely suggests overtones of compulsion in the way the ‘common folk’ (vulgus ) take their stand around the mercatores (20), much as they indeed had forced themselves on the viatores (13) against their will (cf. the linked vocabulary: consistere  and circumsistat ). In terms of the ‘main’ verbs of the uti-clause (beginning at 12), cogant (13) … quaerant (19) chiastically reflect circumsistat (20) … cogant (23) in syntax, and the semantics can’t help but spill over: compulsion (cogant … cogant) thus inheres in quaerant (19), and quaerant inheres in circumsistat (20) – both latter verbs ‘framed’ or ‘enclosed’ as it were by that compulsion.
This example of Caesar’s surpassing stylistic mastery is a useful illustration of the importance of understanding not only the syntax of any sentence but also (especially in the case of longer ones) its structure in order to appreciate the connotations of words and their linkages into networks, or semantic fields. Since the vocabulary of Latin is relatively small, such devices as structural parallelism and its occasional violations are extremely important in helping to load more precisely the varied semantic freight that the comparatively (with modern English) limited lexicon of Latin must shoulder.
In section 4.5 Caesar shows himself consistent in several ways, not least in that sense of superiority about a putative Roman rationality over the barbarians’ alleged fickle emotionalism (mobiles ) and unstable political (novis … rebus ) temperament. But there is also a consistency about his belief in the need for reasoned caution and deliberations based on solid information. The historian Sallust (86-35 BC) has Caesar (100-44 BC) make similar points in the great speech about the punishment of Lentulus that he (Caesar) gives before the senate in the aftermath of the Catilinarian conspiracy (Cat. 51:  magna mihi copia est memorandi, patres conscripti, quae reges atque populi [cf. Gallorum (3) in our passage] ira aut misericordia impulsi [cf. permoti (13)] male consuluerint [cf. in consiliis capiendis (5), consilia ineunt (29)]). To wit, schematically:
pouli Gallorum (3)
impulsi permoti (24)
male consuluerint in consiliis capiendis (5)
consilia ineunt (25)
To be sure, in Sallust’s case the emotional ones were no flighty foreigners but Roman senators partial to Cato’s position! In view of historical events Caesar had already lived through and would endure in the not so distant future, in his implicit impugning of the barbarians as different from the Romans because they, the barbarians, want revolution (novis plerumque rebus student ) there is surely a certain unintended irony that we today may savor … the Romans never had a revolution they didn’t like?
For readers, finally, of a modernist persuasion who delight in excoriating the hegemonic oppression by modern Europe of that dreadfully yclept subaltern, “the other,” this little passage in Caesar opens up a window on how ancient the practice of culturally and militarily driven imperialism is. The notion that some are superior and others inferior is certainly not a de novo invention of decadent Western modernity, nor is it of course — pace post-colonialism’s rigid ukases – even a peculiarly Western one.
What an oppressed Indo-China (Viet Nam), for example, not too many generations ago was to an oppressing France, an oppressed Gaul once was to an oppressing Rome: the oppressed become oppressor. A cyclical view of history, perhaps, the rôles being eternal and only the names changing.
Caesar’s de Bello Gallico its own classic!