Tournesol said:
You need a minor premiss: "I cannot know the outcome without knowing all the determining factors".
F: I don't know all the factors determining a game's outcome.
O: I don't know a game's outcome.
G: I don't know all the factors determining the outcome of the game between Man U and Milan tonight.
P: I don't know the outcome of the game between Man U and Milan tonight.
[(F -> O), F, therefore P] is not valid. Neither are [(F -> O), G, therefore P] or [(F -> P), G, therefore P]. [(F -> P), F, therefore P] and [(G -> P), G, therefore P] are both valid, but (F -> P) isn't true.
If it was meant to be a syllogism, there are bigger problems. For starters, the group of things known appears in all three propositions, so the argument is not valid.
mousesgr said:
i want to ask
1. What kind of argument is the above?
(is it a deductive argument?)
2. How good it is?
1) It is incomplete (and invalid), as Tournesol pointed out. An argument is deductive if the argument being "correct" (whatever standards are set for correctness) guarantees that the argument's conclusion is "correct". Usually, a deductive argument is "correct" or "valid" if it is impossible for all its premises to be true while its conclusion is false. IOW, the truth of the premises guarantees the truth of the conclusion.
2) It's invalid, so not good. But it's not hopeless; If you can add the needed premises, you can make it valid.
In case someone who knows comes along, I'll tack on a question.
premise : i do not know all the factors determining a game's outcome
conclusion : i do not know the outcome of the game between Man U and Milan tonight
Will the following translation work? Let "Kxy" mean "x knows y", "Fxy" mean "x is a factor determining the outcome of y", and "Oxy" mean "x is the outcome of y".