knowledge without conscience is but the ruin of the soul
Here, Rabelais alludes to Soloman and his thoughts on science without conscience. Soloman, the third king of Isreal, was known as one of the wisest and wealthiest men in the Bible (Nelson, 2020). He is known for his writings of multiple books in the Bible, and was very knowledgable on many matters. When he says "knowledge without conscience is but the ruin of the soul", he is basically saying that if we use our knowledge without any care to what is right or wrong, we will ultimately lead to "ruin", rather than improvement in society.
Nelson, R. (2020, August 6). Who was king solomon? the beginner's guide. OverviewBible. Retrieved March 31, 2023, from https://overviewbible.com/solomon/