"Unless" statement Brainfart! Forum

[brooklynballers]

N cannot be selected unless L is selected.

Isn't this supposed to diagrammed as L --> N?

[doyleoil]

N cannot be selected unless L is selected.

Isn't this supposed to diagrammed as L --> N?

just the opposite (meaning, N ---> L)

[artichoke]

No. N--->L

if N is selected, you know L has been as well because N can only be selected if L is.

[brooklynballers]

N cannot be selected unless L is selected.

Isn't this supposed to diagrammed as L --> N?

just the opposite (meaning, N ---> L)

Could you explain the process of getting to your diagram?

[agentcom]

Umm it's been a while, but wouldn't it be:

~L --> ~N

[doyleoil]

Umm it's been a while, but wouldn't if be:

~L --> ~N

This isn't a bad place to start, because I think the best, most common sense, way to get to the diagram is to say to yourself "what happens if L isn't there?" If L isn't there, then N isn't there. And the contrapositive of that is "N ----> L"

[agentcom]

Edit: What doyle said

[brooklynballers]

So you could select L, but not necessarily select N right?

[Jeffort]

So you could select L, but not necessarily select N right?

Yes

[blackwater88]

unless: if not
DONE

[brooklynballers]

unless: if not
DONE

So the best way to think of it would be:

N can not be selected (if not) L is selected
OR
N can not be selected if L is not selected.

Which gives us:
If L is not selected, then N is not selected.

Contrapositive:
N --> L

[Audio Technica Guy]

"if not" works. Some people have just as hard of a time with if not as they do with unless though, and if that is the case, just think "whatever comes immediately after unless goes on the right side, the other thing goes on the left and negated."

[Jeffort]

"if not" works. Some people have just as hard of a time with if not as they do with unless though, and if that is the case, just think "whatever comes immediately after unless goes on the right side, the other thing goes on the left and negated."

I like the 2nd one bolded above more. It is less confusing and faster since it is pretty brainless and mechanical with less translation steps.

[blackwater88]

"if not" works. Some people have just as hard of a time with if not as they do with unless though, and if that is the case, just think "whatever comes immediately after unless goes on the right side, the other thing goes on the left and negated."

I like the 2nd one bolded above more. It is less confusing and faster since it is pretty brainless and mechanical with less translation steps.

To me "if not" works much faster, to be honest I first learned the bolded part, when I thought about "if not" it made me doubt since I didn't grasp the concept of "unless" that well. However, if you just take it as it is and substitute "unless" for "if not" every time it appears, there really is no transitional thinking. Just like you should memorize that all As are Bs = A ==> B

[Unshake]

If you're using the logical reasoning bible, check out page 126 and maybe review all of chapter six. Basically what is explained here is correct; if you see the word "unless" (and some other words like until or except) whatever is modified by this becomes the necessary condition.