I really think that he needs to be in a place where burning his ships is his decision.
No matter how awesome your company is, things are going to get bad. There will be long nights, rejections, technical problems, and failure will loom large. You can make it through this with a good attitude if you really believe in what you are doing. If he is just tagging along with you, I'd worry that he wouldn't have the kind of emotional investment that would see him through the bad times.
But more importantly, I think you would want to bring people into your company that add to the momentum. You want people who inspire you and push you harder. Creative ideas, fresh perspectives, and emotional encouragement aren't going to come from a reluctant, non-committal person who is only there because he burned his ship.
My two cents. =)
Achieving a difficult goal (like building a company) requires a fanatical, passionate determination that does not waver and which drives consistent "do it yourself" behavioral patterns. Independent initiative, determined focus, and unrelenting pursuit of your objectives are not optional.
Surrounding yourself with people who do not carry this same fire will hold you back.
I wrote a blog about this recently, and here is an excerpt:
"Setting an important, ambitious personal goal is the first shot fired in a war of attrition in which the entire world will seek to distract and demoralize you. It is a war for your time and attention, and success depends on the way you storm the beaches of every moment and seize them in the name of your endeavor."
Full entry: http://thinkforrestthink.wordpress.com/2012/10/29/we-slept-o...