Today in class our professor explained that a proposition is a sentence that declares a fact that either true or false but not both. However, shortly after he defined Atomic Proposition as "No part is a proposition" with an example of a proposition.
After researching around it seems that the two are identical as I can't find any definitions that show differences between the two.
A quick and easy explanation between the two would be awesome as I should have asked him during class.
Thanks!
Best Answer
Consider "Grass is green and snow is white".
This is a proposition, since it makes a claim that is either true or false (in our world, it is true, but in other logically possible worlds, it might be false).
However, this statement is not an atomic proposition, since it has a part (e.g. "Grass is green") that is a proposition.
"Grass is green" itself is an atomic proposition, since there is no smaller part that is still a proposition (e.g. "Grass" is not a proposition).