What is your answer?


A valid rule of inference:

    { 1 } - will give a true conclusion when the variables make the premises true.
    { 2 } - has the premises implied in the conclusion.
    { 3 } - cannot have categories for its variables.
    { 4 } - cannot have sentences for its variables.
    { 5 } - is always sound.

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1 is correct!


A valid rule of inference:

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Before continuing, you might try some wrong answers.
























 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

























2 is wrong. Please try again.


A valid rule of inference:

    { 1 } - will give a true conclusion when the variables make the premises true.
    { 2 } - has the premises implied in the conclusion.
    { 3 } - cannot have categories for its variables.
    { 4 } - cannot have sentences for its variables.
    { 5 } - is always sound.

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3 is wrong. Please try again.


A valid rule of inference:

    { 1 } - will give a true conclusion when the variables make the premises true.
    { 2 } - has the premises implied in the conclusion.
    { 3 } - cannot have categories for its variables.
    { 4 } - cannot have sentences for its variables.
    { 5 } - is always sound.

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4 is wrong. Please try again.


A valid rule of inference:

    { 1 } - will give a true conclusion when the variables make the premises true.
    { 2 } - has the premises implied in the conclusion.
    { 3 } - cannot have categories for its variables.
    { 4 } - cannot have sentences for its variables.
    { 5 } - is always sound.

<= back | menu | forward =>
























 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

























5 is wrong. Please try again.


A valid rule of inference:

    { 1 } - will give a true conclusion when the variables make the premises true.
    { 2 } - has the premises implied in the conclusion.
    { 3 } - cannot have categories for its variables.
    { 4 } - cannot have sentences for its variables.
    { 5 } - is always sound.

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the end