Assignment Title
Logical Forms
Logical form 1: No As are Cs. Some Bs are Cs. So some As are not Bs.
No people are wild. Some animals are wild. So some people are not animals.
The conclusion made by this form is not logically valid. The fact that some animals are wild means that some are not. And these not-wild animals can not overlap, overlap, or totally include people. This means that it might be the case that all people are animals which makes the conclusion invalid.
Logical form 2: P only if Q. Q. Therefore P.
Stan wakes up only if the alarm rings. The alarm rang. Therefore Stan has woken up.
The conclusion of this propositional form is logically valid. Stan can only wake up if the alarm rings. This means that there is no other possibility for Stan to wake up other than hearing the alarm ringing. Also, it means that there is no way for Stan not to wake up if the alarm will ring. This is why if the alarm rings then Stan will inevitably wake up, and therefore the form is logically valid.
Logical form 3: If P then Q and R. Q and R. Therefore, P.
If I take steroids, then I will gain muscle mass very fast, and I will have health issues. I'm gaining muscle mass very fast and having health issues. Therefore, I take steroids.
This conclusion is not logically valid. There is a direct causal relationship between taking steroids and gaining muscle mass and having health problems. However, there is no reverse relationship. This means that it is not only steroids that could have caused rapid muscle mass gain and health issues. I could, for example, have started a special diet causing rapid muscle growth and have stress which causing health issues.
