Here is a thought -- when I was learning to ride back in the 80's there were two interesting statistics. One was that on average a rider will have one crash/accident every 10 years. Not too scary. But here is the second statistic I heard back then -- 90% of all motorcycle accidents involve riders with less than a year's experience. Combine those two (I am not sure if it is statistically correct to do so, but it does not matter because the purpose is to get the new rider to think safety), and it become pretty apparent there is a pretty high chance of having your statistically 1 in 10 year accident/crash in your first year. Thus, safety (gear, learning proper technique, keeping a proper lookout at all times, always have multiple "escape routes" when in traffic, etc.) may tend to take on more importance in the mind of the newbie.
Also, as has already been said -- learn from qualified instructors. There are just so many things a new rider does not know and needs to know. For example, riding in the rain (which will happen to everyone sooner or later) requires some knowledge and finesse. Thankfully, I took a lesson on a rainy day -- and I am sure it has saved my butt a few times.
If he won't go to MSF or other formal instruction, then try to mentor him on a few rides. I value learning "on-street and in traffic" survival more than slow speed parking lot work. Generally, the worst that will happen if you haven't practiced the parking lot stuff is you might drop your bike. If you have not learned to survive on the street and in traffic, you can get killed.
Also, if you can find some "motorcycle meets car" pictures on the internet, you may want to show him what happens. I have seen the aftermath of such encounters (both in real life and in pictures). The motorcyclist aways looses, and often it is not pretty. This may help impress the newbie to be more safety oriented.
Just my two cents. YMMV
k_enn