The last rule of inference isuniversal generalization (UG). It has the following form:

_____________

(

We can now state the restrictions on universal generalization. Universal generalization is valid, if, but only if:1.awas introduced by UI or in the assumption of a conditional orreductioproof (not in a premise or by EI).

2. The inference does not occur within a conditional orreductioproof whose assumption containsa.

3. The statement ...a... does not contain any other name introduced by EI on a line containinga.

Universal instantiation | Existential generalization |

Existential instantiation | Universal generalization

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