One of the best ways to find this out would be to make up a bad situation for you (something bad happened to you and you don't know what to do). Ask his advice and see if he gives a caring one or he lacks interest.
Always use your better judgement. Don't view this with your eyes. Take the position of someone on the outside looking in. Men can be smooth talkers, but slick walkers. Never let a man sweet talk you into misery.
You may creat some situations on purpose before him, for example, you pretend to be ill, and you discover his reactions and find out whether he is worried.
