Since nothing exists out of God, his actions do not follow from external necessity, are not constrained, but he is free cause, free in the sense that he does nothing except that toward which his own nature impels him, that he acts in accordance with the laws of his being (_def. septima: ea res libera dicitur, quae ex sola suae naturae necessitate existit et a se sola ad agendum determinatur; Epist_. 26). This inner necessitation is so little a defect that its direct opposite, undetermined choice and inconstancy, must rather be excluded from God as an imperfection. Freedom and (inner) necessity are identical; and antithetical, on the one side, to undetermined choice and, on the other, to (external) compulsion. Action in view of ends must also be denied of the infinite; to think of God as acting in order to the good is to make him dependent on something external to him (an aim) and lacking in that which is to be attained by the action. With God the ground of his action is the same as the ground of his existence; God's power and his essence coincide (I. _prop_. 34: _Dei potentia est ipsa ipsius essentia_). He is the cause of himself (_def. prima: per causam sui intelligo id, cujus essentia involvit existentiam, sive id, cujus natura non potest concipi nisi existens_); it would be a contradiction to hold that being was not, that God, or substance, did not exist; he cannot be thought otherwise than as existing; his concept includes his existence. To be self-caused means to exist necessarily (I. _prop_. 7). The same thing is denoted by the predicate eternal, which, according to the eighth definition, denotes "existence itself, in so far as it is conceived to follow necessarily from the mere definition of the eternal thing."