Information that contradicts my position is forgotten more easily, so note it down at once

Humans have confirmation bias. We give more weight to opinions that match our own.

I am no exception. When designing software, I had never thought deeply about the opposing position, and whenever a logical attack came from that side I could not answer it at all.

I had, also, during many years, followed a golden rule, namely, that whenever a published fact, a new observation or thought came across me, which was opposed to my general results, to make a memorandum of it without fail and at once; for I had found by experience that such facts and thoughts were far more apt to escape from the memory than favourable ones. Owing to this habit, very few objections were raised against my views which I had not at least noticed and attempted to answer. — Charles Darwin (quoted in Sönke Ahrens, How to Take Smart Notes)

To stop missing contrary information, the change has to start at the collection stage. Turn the whole writing process upside down and approach it again, and collect every piece of information regardless of whether it supports or opposes your claim.

Related: Feedback should come more often and be accepted more readily — accepting opposing views is one form of accepting feedback. Related: Account for survivorship bias when reasoning — information that is missing because it is unseen (survivorship bias) or forgotten (confirmation bias) distorts judgment from the same root.