Books like Without Conscience
Robert D. Hare
Without Conscience is 236 pages, about 4 hours 20 minutes at 250 words a minute.
10 books to read next
How long each takes
Psychopath Free 2.8 h 
The Mask of Sanity 9.4 h 
The Sociopath Next Door 4.7 h 
Psychopath Inside 4.5 h 
Bad Men Do What Good Men Dream 6.3 h 
The Wisdom of Psychopaths 5.4 h 
Talking with Psychopaths and Savages 5.1 h 
Confessions of a Sociopath 5.7 h 
The Quake 6.9 h 
Dangerous Personalities 4.7 h Bar height shows length. Estimated at 250 words a minute.