Hi,
I have this argument: "Because we locked the door, no one can break into our house."
The book says that this is not a necessary assumption: "The door is the only way in and out of the house, and the lock impenetrable."
But I thought that if the door is not the only way in/out and the lock is penetrable then you can't really say that if you lock the door no one can break into your house.
Can someone please explain to me why that assumption is not necessary?
Thank you!
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3 comments
This is a helpful discussion on this topic:
https://classic.7sage.com/discussion/#/discussion/19951
@cnavarro495649 said:
This is a helpful discussion on this topic:
https://classic.7sage.com/discussion/#/discussion/19951
Thank you @cnavarro495649 - really helpful and I will bookmark it!
I just want to make sure my reasoning is correct: is D not required because even though "The door is the only way in and out of the house..." is required "...and the lock is impenetrable" is too strong- is the reason it's too strong is because even if it is penetrable there could be other security features in the door besides the lock that will prevent potential robbers from breaking in?
@cnavarro495649 Not sure if you still need this but I'm just gonna say it here because the link provided is broken. Basically the issue is the difference between REQUIRED and SUFFICIENT. "The door is the only way in and out of the house" is required because the argument is done for if we negate it. But once we add "locked door is impenetrable" it becomes sufficient because it's too much, since the argument simply does not require that second part to be true along with the first part (only the first part is enough). If it's by itself it would be a required and less important assumption.
If you check the second example about the caffeine, the book included "very tempting, but more than we need" to the assumption that is quite similar to this one.