This construction is the result of an interesting history which has been reconstructed by linguists. According to current thinking, it goes like this. Many verbs that take the accusative-infinitive phrase which we see in indirect discourse can take a simple accusative object as well. volo te = I want you. cogo te = I compel you. iubeo te = I order you. At an early point in the history of Latin, the abstract verbal noun had case endings, just like other nouns. In Latin it was the dative or locative ending which became associated with the infinitive. This means the the infinitive expressed an adverbial idea, something like "with reference to" or "in the area of." Thus one could say "In reference to going (ire) I have a desire (volo)" = volo ire = "I want to go." Or one could say "In reference to going (ire) I compel you (cogo te)" = cogo te ire = "I compel you to go." It was in expressions like this last one that linguists believe the accusative-infinitive phrase became (falsely, at it appears) identified as a separable unit: te ire could be the object of cogo, of volo, of iubeo, and eventually of dico.