In Hebrew, the definition of "presume" is to move or make decisions arrogantly. Webster's Dictionary says it means "to act or behave with undue boldness." In other words, when we act before knowing ALL the facts from EVERY side, we are acting presumptuously and arrogantly. Many times, it's impossible to know the full story if we cannot talk directly to the person we are making a presumption about. This is why we are to never judge a person or situation unless we are in a position of authority to do so. If we do, we will be judged in the exact same way in which we chose to judge.
Presumption destroys relationships. In my opinion, it's the #1 reason relationships go south, arguments escalate, and close friends separate. So what's the answer? The #1 answer for the #1 problem is: ALWAYS ASSUME YOU ARE MISSING INFORMATION. Period. Never judge someone until you've given them the chance to fill in all the missing information. When you think the best about your spouse, friend, or even something you hear on TV, refusing to presume or come to conclusions before gathering all the information, you will most likely discover that you saved not only the relationship but the humiliation of having to eat humble pie when you learn all the information you didn't even know you were missing. And even after you get all the information and find that the person really messed up, STILL don't judge. Pray for them. That's our job as lovers of the brethren (Mt. 5). Even Christ doesn't judge until Judgment Day. Until then, He chose to die for them.
Bottom line? Stop presuming and judging one another. That's what the heathens do. We love. We pray. We cover. And we let YAHWEH be the Judge. You dig? ;-)