"There are many members of parliament present here who know as well as I do that, if a man has not already been converted, it will require a great deal more than a letter of appeal to achieve conversion"

This quote by Fredrik Bajer is describing the problem of convincing individuals to alter their beliefs or viewpoints. He is suggesting that it is not enough to just send a letter of attract somebody in order to get them to change their mind. He is implying that it will take more than just a letter to convince someone to convert, which the members of parliament present at the time would comprehend this. This quote is emphasizing the significance of putting in the time to effectively describe and talk about a concern in order to get somebody to alter their viewpoint. It is likewise recommending that it is not constantly easy to get somebody to alter their mind, which it may take more than simply a letter of appeal.