The further one delves into the study of the Ripper murders, the easier it becomes to imagine them through Jack's eyes. What did he feel in the hours before he murdered, while he hunted for victims? Perhaps he toyed with the women, buying them drinks in pubs like the Brittania and then leaving their company, only to meet up again one last time later that evening. He must have been giddy with power, believing that he held in his hands the fate of each woman he passed.
We will never know the veracity of these ideas. But there are some safe assumptions about the Ripper and his personality that criminology -- both contemporary and modern -- has provided.
As the slayings continued, Jack the Ripper's modus operandi (M.O.) -- the methods he used in each murder -- became clear. He struck only in the early hours of morning and only on weekends. These facts are revealing. For one, they suggest the Ripper was single, since he was able to keep late hours without arousing suspicion. Secondly, they point to the idea that he was likely regularly employed during the week (which would explain his inactivity Monday through Thursday) [source: Bardsley].
The manner with which he dispatched his victims also contained clues. All but one woman was killed by strangulation. Once laid carefully on the ground, the Ripper cut the victim's throat, beginning with the side facing away from him. This effectively drained the blood from his victims before he began the ritual evisceration. Much of the organ removal was done cleanly. In the case of Eddowes, the Ripper removed the left kidney from the front, rather then the back or side [source: Barbee]. Altogether, the eviscerations and organ removals suggest the Ripper was a person with some form of anatomical or surgical training. The knife wounds inflicted also indicate that he was right-handed [source: Bardsley].
Based on historic witness accounts, modern investigators at Scotland Yard compiled a physical description of the killer in 2006. He was a man between 25 and 35 years of age, of medium height and stocky build. Investigators also concluded that Jack was a resident of Whitechapel and, more chillingly, that he was "frighteningly normal," as opposed to the raving, drooling fiend it may be more comforting to imagine [source: BBC].
In 1988, the FBI created a psychological profile of Jack the Ripper. Special Agent John Douglas concluded that the Ripper was an opportunistic killer: He preyed on alcoholic prostitutes because they were easy targets. Douglas also believed that the Ripper committed other crimes which were never definitively attributed to him. Jack was a lust killer, meaning that the focus of his ritual mutilations was the female genitalia. This doesn't mean the murders were sexual; there's no evidence the Ripper engaged in sex with his victims before or after their murders (although the agent believes Jack frequented prostitutes). Rather, the mutilations suggest that he was acting out violent fantasies aimed toward his mother. His mother likely provided the image Jack had of women, one which he came to despise. She may have been an alcoholic -- and possibly a prostitute herself [source: FBI].