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Rule I reached its final form in the Second Edition, where it was also transformated from an Hypothesis to a Rule. The Rule later became known as the "vera causa" principle. The final version reads:

The revisions:

	English
Principia (1687)	Hypoth. II. Therefore, the causes assigned to natural effects of the same kind must be the same. Examples are the cause of respiration in man and beast, or of the falling of stones in Europe and America, or of the light of a kitchen fire and the sun, or of the reflection of light on our earth and the planets.
1690s Revisions	E2i: Hypoth II. Rule II.
Principia (1713)
1710s Revisions	E2i & E2a: Unless their diversity (unless perhaps a certain diversity) ((unless a certain diversity be rendered manifest by the phenomena)), these causes suffice to explain the phenomena.   This entire clause is crossed out for the published "so far as possible", and in E3.
Principia (1727)	Rule II. Therefore, the causes assigned to natural effects of the same kind must be, so far as possible the same. Examples are the cause of respiration in man and beast, or of the falling of stones in Europe and America, or of the light of a kitchen fire and the sun, or of the reflection of light on our earth and the planets.

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