I'm going to encourage my wife to breastfeed
That's a very natural thing. Is your wife against breastfeeding?
No, she just hasn't decided, but I think it's best for our baby.
You sound like you will be a very good parent. Go ahead and encourage your wife to breastfeed, but let her make the final decision.
What if she decides to feed him artificially?
It's still her choice in the end, because not all women are able to breastfeed. Sometimes it can be very painful! I'm sure with whatever you feed the baby, you'll be taking great care of it.