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A '''valid argument''', in [[formal logic]], one in which the conclusion is correctly derived from the premises. That is, a valid argument is one in which, if the premises are true, the conclusion must also be true. A valid argument whose premises are true is called a '''sound argument''', and its conclusion must be true. A valid argument whose premises are not all true is called a '''valid but unsound argument''', and its conclusion is not necessarily true.

A '''valid argument''', in [[formal logic]], one in which the conclusion is correctly derived from the premises. That is, a valid argument is one in which, if the premises are true, the conclusion must also be true. A valid argument whose premises are true is called a '''sound argument''', and its conclusion must be true.

 

A valid argument whose premises are not all true is called a '''valid but unsound argument''', and its conclusion is not necessarily true. The following is an example of a valid but unsound argument, in which one of the premises is untrue, so that the conclusion cannot be relied upon (and is wrong):

*Therefore, grass tastes like limes.

{{quotebox|A deductive argument is said to be valid when the inference from premises to conclusion is perfect.  [http://www.philosophypages.com/lg/e01.htm Arguments and Inference: truth and validity] }}

{{quotebox|A deductive argument is said to be valid when the inference from premises to conclusion is perfect.  [http://www.philosophypages.com/lg/e01.htm Arguments and Inference: truth and validity] }}

[[Category:Logic]]

[[Category:Logic]]