¿Posees ya el uso de razón?
This is a name of a book's section: ¿Posees ya el uso de razón?
I was not sure about the meaning of a whole phrase so surfed the dictionary, but it seems that it can be understood in few ways, like - Have you already got the use of reason? As I understand, "poseer uso" can mean "to become acustomed"? So then Are you already acustomed to reason (or to truth)?
Opinions and suggestions please
uso de razón link 1 uso de razón = Capacidad para pensar y para juzgar que consigue una persona cuando ha pasado la primera etapa de la niñez: desde que tengo uso de razón recuerdo a mi padre fumando puros.
poseer - means "to possess/own" or, in this case, "to master" may be better...
This still leaves me with no particularly good way to translate "uso de razón" exactly into English. I don't think I'd ever say "use of reason" but I suppose that might work.
So, maybe, "Have you mastered the skill of reasoning yet?" or "Do you have the capacity to think for yourself yet?"
Some possibilities for your sentence ¿Posees ya el uso de razon?
Do you have the ability to think (abstractly) yet?
Have you reached the age of reason yet? This concept refers to Alba's first link for uso de razon. It's the notion that a child reaches or attains the age of reason at around 7 years old. The Catholic Church uses this age to distinguish when a child begins to know right from wrong intellectually. Interestingly, cognitive psychologists such as Piaget also considered age 7 as the start of the stage of formal reasoning, which would lead to the ability to think abstractly.
"Desde que tengo uso de razón recuerdo a mi padre fumando puros."From the time I reached the age of reason, I remember my father smoking cigars."
- If the book is written for children, the question may simply be asking if the child can think and reason things out.