Click here and press the right key for the next slide (or swipe left)
(This may not work on mobile or ipad. You can try using chrome or firefox, but even that may fail. Sorry.)
(If the slides don’t work, you can still use any direct links to recordings.)
also ...
Press the left key to go backwards (or swipe right)
Press n to toggle whether notes are shown (or add '?notes' to the url before the #)
Press m or double tap to slide thumbnails (menu)
Press ? at any time to show the keyboard shortcuts
Philosophy is done by asking questions.
Sam W
In regard to Hempel's ravens, I was curious why the case of an example of not-G and not-F is not [evidence that] everything that is F is G.
While it is true that the evidence is significantly weaker [...] it doesn't contradict the claim and therefore at least facilitates its potential truth.
Could you explain exactly why we should be unhappy with the observation of not-F and not-G providing "proof" of everything that is F being G
1. Every observation of something which is neither a raven nor black is evidence for all ravens are black.
2. Some observations of something which is neither a raven nor black are evidence for all ravens are two.
1. Any observation of an instance is evidence for the generalisation.
2. Any evidence that confirms a generalisation also confirms any logically equivalent generalisation.
3. ‘I have often seen white shoes; therefore all ravens are black’ is a bad argument.
3. ‘When looking for non-ravens, I have often seen white shoes; therefore all ravens are black’ is a bad argument.
1. Every observation of something which is neither a raven nor black is evidence for all ravens are black.
2. Some observations of something which is neither a raven nor black are evidence for all ravens are two.
Sam W
In regard to Hempel's ravens, I was curious why the case of an example of not-G and not-F is not [evidence that] everything that is F is G.
While it is true that the evidence is significantly weaker [...] it doesn't contradict the claim and therefore at least facilitates its potential truth.
Could you explain exactly why we should be unhappy with the observation of not-F and not-G providing "proof" of everything that is F being G
Walsh, Sam
Is it logically plausible that we could construct properties like grue, but which contradict some fact that is assumed in the assessment of the truth of forms?
Mr Walsh
1. All grue objects I have observed are green.
Therefore:
2. All grue are green.
‘Surely here, the observation is at fault’
more questions?