Hi. I think you should absolutely start! I would let my daughters run around w/nothing on their bottoms and when they started peeing I'd just move them over to the potty (I had to be RIGHT THERE always, so that was a bit tiring, but they "got it" quickly). I'd congratulate them if they got ANY in the potty and just quietly clean up the mess when there was some.
I started training each daughter at 18 months and both were 100% done for daytime by the age of 2. I don't think 23 months is too young at all! (One was done at night by 2 1/2 the other is almost 3 right now and still needs a diaper at night).
Take advantage before he changes his mind!!
