I came up with an idea that may be a safe way of gauging your discipline.
Open a card with a credit limit of $500, at most $1,000. See if you can pay off the entire balance every month for a year or two. If you never carry a balance, then maybe request an increase on the credit limit.
If you max out a $1,000 credit limit, I don't see a reason to think you won't max out a $50,000 credit limit. If you think otherwise, you are likely very disillusioned.