It depends what kind of work you'll be doing with Logic.
But on the other hand, Logic doesn't depend on a discrete graphics adapter like film/video post production software.
Maybe you can get an external sound card (USB) to handle many, many tracks if you have to, but other than that, I do think the MacBook is quite good in handling Logic.
I started with Logic (when it was still Emagic's software) with a Pentium 3 with around 700 MHz and an Audiowerk card, and it worked more than okay, but I was only working with spoken words and no music recording and editing (features for radio stations).