3. The breach of the duty caused the injury.Gene and Alan have used the concept of
proximate cause. They merely have used understandable English rather than legal jargon. Contrary to what you may be thinking, this choice to omit jargon is not a reason to report the lawyers to their respective bar aaociations.

Say I, a teacher, owe a student the duty of keeping the gymnasium environment safe. (This hypothetical requires a huge suspension of disbelief, a number of belt promotions for me, and a gym and students, but bear with me.

)
Say the mats are faulty, and I know it. I have not repaired them. This is a breach of that duty.
Say a home/gym invader comes in uninvited, unexpected, and brains my student with a baseball bat. He is injured; there are damages.
But these damages are
not due to my breach of duty by having unsafe mats. There was an
intervening and superseding cause of his injury: the thug with the bat. The thug is wholy responsible.
Now, suppose my student was knocked off his feet and fell onto the faulty part of the mat. He becomes injured again, because the mats were faulty. Was my breach of duty a cause of this injury?
Yes. While it is not generally
foreseeable that your dojo will be invaded (now that John Keehan has been dead for over a decade

), it is foreseeable that someone will fall on a mat used in martial training; that is the purpose of such mats. If the mats are faulty, it is foreseeable that someone will be injured in the fall.
If an injury is so unlikely that it is unforeseeable, one should not be held liable for not having taken unreasonably high precautions against it.
Now one gets into the delightful concepts of
multiple causation, apportionment, and
comparative/contributory negligence. But that's for another post.
Damn; almost like being in law school again....

student
[This message has been edited by student (edited March 15, 2002).]