Joiner was a graduate student when his father took his own life - an event that came as a shock to his family and friends
Joiner says, "Just like heart disease, if you understand it, you can prevent it."
In a groundbreaking theory outlined in his new book, "Why People Die By Suicide," Joiner says that those who kill themselves not only want to die, they have learned to overcome the instinct for self-preservation.
In Joiner's theory, suicide victims literally "work up" to the act by getting used to danger, fear and pain. They may do this in a variety of ways over their lifetime.
They engage in reckless behavior, cut or otherwise hurt themselves or have repeated suicide attempts.
Others may have a history of accidents or medical procedures while still others become inured vicariously.
Perhaps like physicians - who have an elevated risk of suicide - they are exposed through their work to pain and suffering on a daily basis.
Joiner says, "Some people think that those who commit suicide are weak. It's actually about fearlessness. You cannot do it unless you are fearless, and this is behavior that is learned."
But knowing the risk factors makes prevention possible, Joiner says, that maintaining good interpersonal relationships is essential. This is perhaps the downfall of many older white men - the demographic that has the highest suicide rates of all.
