The Malbim interprets this verse to mean that the clever person will find ways to resolve doubts, but the fool will create new ones.
The doubts to which the Malbim is referring are those that relate to Torah and mitzvos. A person who feels that observance of the mitzvos is an imposition may look for ways to justify non-compliance, and may do so by casting doubts on their validity. He may find what he feels to be inconsistencies, or argue that science challenges Torah principles. However, he succeeds in deceiving no one other than himself. Everyone else knows that he is not motivated by a search for truth, but merely by a desire to avoid any inconveniences.
A clever person, who may be subject to the same arguments, will realize that all of the objections of which he can think were known to greater minds than his. Our history is replete with intellectual giants and philosophical geniuses, whose absolute dedication to Torah and mitzvos was not affected in the least by all the challenges which may appear so cogent. One can safely rely on their conclusion that after considering all arguments, they concluded that the teachings of Torah were correct.
The person who uses arguments to evade Torah observance is placing his mind above that of the intellectual giants of our heritage. Only a fool would do that.