He said: "Well, you've never had a good grasp of logic, SO this can't be true."
Which is the same as saying: "This can't be true, BECAUSE you've never had a good grasp of logic."
The problem with ad hominem attacks is a broken clock can be correct twice a day or more. So saying the clock is broken does not necessarily imply that it's wrong now just that it has been wrong in the past and will probably be wrong in the future.
When parsing arguments look for words like and, or, because, so, thus, etc as they are the foundations of arguments. You can add a lot of meaningless drivel around the core argument but as soon as someone starts tossing those words around they are probably trying to use logic. His point is the way an attack is connected to the argument determines if calling something ad hominem discredits the argument.
PS: People sometimes add an ad hominem attack as part of other more rational statements, so IMO attacking the person even alongside a rational argument is still an ad hominem attack even if it is not used to directly attack their argument. However, simply calling part of what someone says an ad hominem attack does not destroy the rest of the argument if it's not directly linked to it. It's like a defense attorney that counters the DNA evidence but ignores the video tape and the confession is going to fail.
The problem being is that not having a good grasp of logic can cause you to reach wrong conclusions. It can be a direct cause. In which case, it is a valid point to bring up as it supports your argument.
Knowing the cause is useful, but to discredit someone's argument you need to find the mistake. Think million monkey's typing for a million years randomly recreating Calculus. The source is dumb but it works.
Which is the same as saying: "This can't be true, BECAUSE you've never had a good grasp of logic."
The problem with ad hominem attacks is a broken clock can be correct twice a day or more. So saying the clock is broken does not necessarily imply that it's wrong now just that it has been wrong in the past and will probably be wrong in the future.
When parsing arguments look for words like and, or, because, so, thus, etc as they are the foundations of arguments. You can add a lot of meaningless drivel around the core argument but as soon as someone starts tossing those words around they are probably trying to use logic. His point is the way an attack is connected to the argument determines if calling something ad hominem discredits the argument.
PS: People sometimes add an ad hominem attack as part of other more rational statements, so IMO attacking the person even alongside a rational argument is still an ad hominem attack even if it is not used to directly attack their argument. However, simply calling part of what someone says an ad hominem attack does not destroy the rest of the argument if it's not directly linked to it. It's like a defense attorney that counters the DNA evidence but ignores the video tape and the confession is going to fail.