The seventh virtue is simplicity. Antoine de Saint-Exupery said: "Perfection is achieved not when there is nothing left to add, but when there is nothing left to take away." Simplicity is virtuous in belief, design, planning, and justification. When you profess a huge belief with many details, each additional detail is another chance for the belief to be wrong. Each specification adds to your burden; if you can lighten your burden you must do so.
This is true. But it's only partially true, in my experience. Beliefs are complex, because the objects of belief are complex. Reduce each element of your belief, analyze it, understand it. Then move on to the next. Don't cut out things for fear of being wrong. It's more work and takes longer, but you'll find you've learned more by the time you finish.