progressiveman1

If you use intelligence for justification instead of observation, wouldnt that be considered a priori? For example, you know basic addition from observation, but justify more complex problems by using your mind independent of observation. Only the genesis of your knowledge would be based on observation(a posteriori), but after that it would be based on no observations(a priori). I just started it yesterday. Its kind of confusing, but I'll keep at it.

She implied in AS that "greed" wasnt a concept by purposely showing there is no specific definition of the word. Either way, we can use the word "greed", "extremism", or any anti-concept for the example. I read that passage in ITOE yesterday and based on my knowledge, I cant agree with her that they should be called "invalid concepts." How can it be a valid/invalid concept if its not a concept at all? For example, if one of our senses doesnt provide accurate knowledge of the world then it would be considered an invalid sense. With her definition of "invalid concept", isnt Rand describing words that arent concepts in the first place?

Lets see if I understand. The senses can be called "valid" because the purpose(the reason for which something exists) of them is to provide accurate knowledge of the world. The senses would be called "invalid" if they provided inaccurate knowledge of the world because it would go against its purpose. I'm still confused why Ayn Rand said a concept could be valid or invalid. An invalid concept(for example, the word "greed") is not a concept at all. If its not a concept, how can it be considered an invalid concept?

Did Kant think all actions should be based on selflessness, or was that just his take on goodwill? (A direct quote would be best). It seems like his philosophy is based on "duty", but that doesnt necessarily always mean duty to others. He says humans should act with duty to obey all universal laws, which I understand 'duty' to mean an obligation if one expects to be moral. So I assume Kant thought each motive of action should be based on duty to universal laws, but did he ever give his answer to why that should be the motive?

The examples they used as a priori: "All bachelors are unmarried. All triangles have three sides." How is that a priori? Also, the example under "Intuitive Distinction" on wiki.

I was having a discussion with a guy who tries to lower Ayn Rand's reputation because he thinks she used terms incorrectly. One of the things he pointed out was that Rand called the senses valid and she called concepts valid. His point is that they are not "valid", they just are. I think, and I think he agrees, that the senses provide accurate knowledge of the world, but should they be called "valid"? For concepts, should a concept be called valid/invalid, as opposed to just 'concept' or not a concept? 1. What does "valid" mean? 2. Are the senses valid? 3. Are concepts valid?

It seems like a lot of people mean a priori to be how its explained on wikipedia: http://en.wikipedia.org/wiki/A_priori_and_...ri_(philosophy) Why is that meaning wrong?

Some people use the term a priori as: "A priori describes truths justified by Reason. In other words, knowledge is a priori if its justification condition is independent of experience." How do you know this isnt the correct meaning of the word?

How do you know thats the correct meaning of a priori?

What are necessary and contingent propositions?