change must be effected either by the thing itself or by some other thing?
Most certainly.
And things which are at their best are also least liable to be altered or discomposed; for example, when healthiest and strongest, the human frame is least liable to be affected by meats and drinks, and the plant which is in the fullest vigor also suffers least from winds or the heat of the sun or any similar causes.
Of course.
And will not the bravest and wisest soul be least confused or deranged by any external influence?
True.
And the same principle, as I should suppose, applies to all composite things—furniture, houses, garments: when good and well made, they are least altered by time and circumstances.
Very true.
Then everything which is good, whether made by art or nature, or both, is least liable to suffer change from without?
True.
But surely God and the things of God are in every way perfect?
Of course they are.
Then he can hardly be compelled by external influence to take many shapes?
He cannot.
But may he not change and transform himself?
Clearly, he said, that must be the case if he is changed at all.
And will he then change himself for the better and fairer, or for the worse and more unsightly?
If he change at all he can only change for the worse, for we cannot suppose him to be deficient either in virtue or beauty.
Very true, Adeimantus; but then, would anyone, whether God or man, desire to make himself worse?
Impossible.
Then it is impossible that God should ever be willing to change; being, as is supposed, the fairest and best that is conceivable, every God remains absolutely and forever in his own form.
That necessarily follows, he said, in my judgment.