logic question Forum

[winnatech]

Hi,

If there is a condition that is "All A are B", does that also mean that "some B are A" as well? Thanks.

[stargazin]

Yes. It's that "inference ladder" thing. A --> B also means A <--some--> B.

[Anaconda]

Correct.

Ex)

All MLB all-stars are baseball players.

You can infer that some baseball players are all-stars, but you can't imply that ALL baseball players are all-stars.

[gdane]

You must remember that when you have an If A then B statement, SOME B are A, but not ALL B are A.

If youre confused about conditional reasoning go over that section in the logical reasoning bible and there's a conditional reasoning guide here on TLS that is also helpful.

Good luck!

[tamlyric]

Strictly speaking, no. But, assuming that at least one thing is A, then yes. Since LSAC probably doesn't worry about the situation in which nothing is A, I think it's a pretty safe bet that "All As are Bs" entails "Some B is A." So, for example, if all politicians are liars, then at least one liar is a politician--i.e., assuming that there is at least one politician.

[dub]

Strictly speaking, no. But, assuming that at least one thing is A, then yes. Since LSAC probably doesn't worry about the situation in which nothing is A, I think it's a pretty safe bet that "All As are Bs" entails "Some B is A." So, for example, if all politicians are liars, then at least one liar is a politician--i.e., assuming that there is at least one politician.

Right. In LSAT logic, if a word for something exists, that something exists.

[lawgod]

There could be no A.

My system: Forget the rules and just think about what makes sense.
(easy for me to say, I'll never take another LSAT)

[arean.ryan]

[094320]

..

[op-ti]

You must remember that when you have an If A then B statement, SOME B are A, but not ALL B are A.

If youre confused about conditional reasoning go over that section in the logical reasoning bible and there's a conditional reasoning guide here on TLS that is also helpful.
Good luck!

Really?

Does anyone have a link to this?

[Dany]

You must remember that when you have an If A then B statement, SOME B are A, but not ALL B are A.

If youre confused about conditional reasoning go over that section in the logical reasoning bible and there's a conditional reasoning guide here on TLS that is also helpful.
Good luck!

Really?

Does anyone have a link to this?

http://www.top-law-schools.com/conditio ... oning.html

-I don't know if that was the one being referenced, but it's the only one I know of on here.

[op-ti]

You must remember that when you have an If A then B statement, SOME B are A, but not ALL B are A.

If youre confused about conditional reasoning go over that section in the logical reasoning bible and there's a conditional reasoning guide here on TLS that is also helpful.
Good luck!

Really?

Does anyone have a link to this?

http://www.top-law-schools.com/conditio ... oning.html

-I don't know if that was the one being referenced, but it's the only one I know of on here.

THANK YOU eskimo!