Positive and Negative Rules in Membership Setup


I have a site that was using a different membership plugin, and I am working on setting it up with Membership. We technically only have 1 level (you are a member, or you are not). But from what I see I will need to create 3 access levels – 1 for visitors, 1 for our Free Samples, and 1 for Members (correct?)

My question is more about the positive and negative rules. If I want Members to be able to access members only pages plus any public pages, but visitors to only have access to public pages, can I accomplish this with just negative rules – by placing a negative rule in visitors blocking them from the Members only pages? Or do I have to set a positive rule for all pages too?

Hope that makes sense. Thanks – Matt