You cannot create a harvest that will feed you solely by deciding what not to plant.
No matter how many crops you reject, nothing magically grows until you decide on one that you do want, and plant it. Saying, “I don’t want corn, I don’t want potatoes, I don’t want wheat, I don’t want lettuce…” enough times doesn’t make tomatoes sprout.
Narrowing your own possibility space will not create anything. It should never be your first move. Your possibility space will naturally narrow as you make affirmative choices, but the reverse isn’t true – affirmative choices won’t get made as you reject options.
The Opportunity Machine 