Just a quick question,
Can the word "premise" mean unspoken assumption? Or is it at all times only mean evidence.
Thank you (:
Premise = Assumption ? Forum
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Ron Howard
- Posts: 207
- Joined: Tue Jul 07, 2015 8:01 pm
Re: Premise = Assumption ?
A bit of the other way, actually. An assumption can be thought of as an unspoken premise. If it is a sufficient assumption, then it is something, which if it were given as a premise, would leave one compelled to the accept the truth of the conclusion; at the same time, while sufficient to guarantee the conclusion, it is not required. If, however, it is a necessary assumption, then it must exist in order for the conclusion to logically follow; yet the mere fact that is exists is not sufficient to guarantee the truth of the conclusion.
Example 1: If a thing has feathers, then it is a bird. A Sparrow is a type of bird.
Premise: If a thing has feathers, then it is a bird.
Conclusion: A Sparrow is a type of bird.
Sufficient Assumption: A Sparrow has feathers.
Notes: Since we know (from the premise) that any thing that has feathers is a bird, we can deduce (know for sure) that a Sparrow is a type of bird if we know that it is has feathers. Thus, if we assume that a Sparrow has feathers, we have something that is sufficient to conclude that a Sparrow is a bird.
Example 2: If something is a bird, then it has feathers. A Sparrow is a type of bird.
Premise: If something is a bird, then it has feathers.
Conclusion: A Sparrow is a type of bird.
Necessary Assumption: A Sparrow has feathers.
Notes: Given the premise, it is not possible that a Sparrow could be a bird if it did not have feathers. In other words, a Sparrow could be bird only if it had feathers, so this is necessary for the conclusion to hold. But also note that just because a Sparrow has feathers, we need not conclude that it is a bird.
Example 1: If a thing has feathers, then it is a bird. A Sparrow is a type of bird.
Premise: If a thing has feathers, then it is a bird.
Conclusion: A Sparrow is a type of bird.
Sufficient Assumption: A Sparrow has feathers.
Notes: Since we know (from the premise) that any thing that has feathers is a bird, we can deduce (know for sure) that a Sparrow is a type of bird if we know that it is has feathers. Thus, if we assume that a Sparrow has feathers, we have something that is sufficient to conclude that a Sparrow is a bird.
Example 2: If something is a bird, then it has feathers. A Sparrow is a type of bird.
Premise: If something is a bird, then it has feathers.
Conclusion: A Sparrow is a type of bird.
Necessary Assumption: A Sparrow has feathers.
Notes: Given the premise, it is not possible that a Sparrow could be a bird if it did not have feathers. In other words, a Sparrow could be bird only if it had feathers, so this is necessary for the conclusion to hold. But also note that just because a Sparrow has feathers, we need not conclude that it is a bird.
