In Bacon's essay "Of Studies," he lists the profound benefits and the vain applications of scholarly work and study. When Bacon writes "to use them (studies) too much for ornament, is affectation," he means that one should not study and read just to show off. Referring to the quote you cited, one should not just read to show off or simply to be involved in academic circles or conversations. In other words, one shouldn't study just to "find talk and discourse."
A person shouldn't read/study just to find opportunities to prove others wrong ("read not to contradict and confute"). What you learn should have a significant or maybe even a profound effect on your life. Therefore, to learn something and not apply it ("to believe and take for granted") is not only a waste of time; it also shows you don't have the willingness to use knowledge at all. If you're going to learn, use what you learn.
Bacon continues by describing how some books require diligence and attention while others are "distilled" (lacking deep meaning, watered down) and not as important. Bacon finishes the essay noting how studies should supplement areas where men (people) are deficient. For example, "if a man write little, he had need of a great memory." Also, more specific to a study, "if a man's wit be wandering, let him study the mathematics."
A person must "weigh and consider" what he studies; it should have a significant effect on how he/she thinks and how he/she applies these learned truths to his/her personal and social life. A person must also "weigh and consider" what to study. Some books are trite; some are profound. Bacon encourages a well-rounded scholarship but he does imply that one should focus on his/her weaknesses. "So every defect of the mind may have a special receipt."
Bacon implores everyone to study for the sake of truth; not to show off, be involved in intelligent conversation, or simply to make arguments to prove someone wrong. Proving someone wrong in an argument (or court case) is worthwhile if it is in pursuit of truth or justice, but it is useless if you're just trying to belittle the other person to make yourself look intelligent.
What you study and what you intend to do with what you learn should be weighed and considered. In other words, you should think about what you study and why you study it. Studying simply to sound intelligent (in order "to contradict" or "find talk") is superficial. Weighing and considering what you learn leads to deeper personal development and, when a conversation does present itself, will lead to meaningful "talk."