What point is Casca making when, referring to a group of women, he says, “If Caesar had stabbed their mothers, they would have done no less”? (p. 31, lines 280-286)

Casca was talking about when Caesar had an epileptic attack. Caesar tells the women to excuse anything he might have said during the attack. Casca points out the common women believe any excuse that Caesar gives: they are star struck. Casca adds that Caesar could have stabbed their mothers and the women would have believed his excuse.