Rational empiricist who believed that madness was caused by a conflict between drives and moral codes

Your question implies two different philosophical currents:

The empiricism is the philosophical current that considers the experience as the rule of truth regarding knowledge;  it refers to the “experience” as the act of repeated situations in life (objective and impersonal) that allow us to gain knowledge of things or situations in life. Mainly, the empiricism denies the absolute truth as it is not accessible to the common men. Acknowledge, though that every truth shall be tested and through experience eventually modified, corrected or abandoned. It does not oppose to the reason but rejects the “necessary truth” in other words, those truths that could not be questioned by any means (dogmas). Mainly we act and conduct ourselves through this manner using customs or habits, against the rational approach, in which everything is questioned.

On the other hand, the rationalism considers that reality is governed by an intelligible principle where reason can reach a meaning and identifies reason with thinking. In general, terms, when you talk about the ethical rationalism, it is named Socratic moral intellectualism. Also, there is the metaphysic or platonic rationalism which considers that the ordered reality is ruled by the ideal and final model of goodness; there is also the religious rationalism, leader by Kant among others which relies on the influence of a rational God, the ontological rationalism (drawn by Hegel) which line up reality with the self-realization of the spirit. All the different varieties of rationalism have in common that consider a reason not a faculty but a concatenation of necessary truths.

Therefore, “A Rational empiricist” does not exist, both currents are in a certain way exclusive to each other. Nevertheless, the phrase you mention: “madness was caused by a conflict between drives and moral codes” Can correspond to an approach provided by the metaphysic rationalism.  

As mentioned, the “ideal of goodness” determined by what is morally consider right or wrong by the human’s established codes (in a certain time, as morality has a temporary nature) can generate a conflict in a person; (what is taught vs. what is desired) to the point of madness, particularly if the beliefs had been deeply rooted during growing and  inserted into somebody’s mind as rules of correctness, against which a person cannot act without punishment or disparateness of beloved ones or society.

Greetings!

the answer is solomon northrup. he was a free-born african american, abolitionist and professional violinist that was drugged, kidnapped and sold as slave in 1841 and remained in captivity until 1853 where he regained his freedom with the of the then-governor of new york, washington hunt. he wrote and published his memoirs "twelve years a slave" in 1853, and in this text, he tells the story of his escape thru one of louisiana's swamps (the great pacoudrie swamp) in which he ended up covered in green slime from crossing the surface of the dead water.