Una nota sul dativo di vis (a proposito di Cic. Arat. 70)

In Cic. Arat. 70 nec vi signorum cedunt we find a nearly sure example, which has gone so far totally unnoticed and is not recorded by dictionaries and grammars, of the singular dative of the normally defective noun vis. This form, whose only other literary occurrence is found in the Bellum Africum, is likely to be understood as a morphological archaism. Its use by Cicero can also corroborate an old conjecture of Timpanaro on a problematic passage of Lucretius’ De rerum natura (1, 453, aquae vi for aquai).