The seed of a tree has the nature of a branch or twig or bud. It is a part of the tree, but if separated and set in the earth to be better nourished, the embryo or young tree contained in it takes root and grows into a new tree.

...from the same principles, I now demonstrate the frame of the System of the World.

I do not think that this [the universe] can be explained only by natural causes, and are forced to impute to the wisdom and ingenuity of an intelligent.

[1.] And first I suppose that there is diffused through all places an aethereal substance capable of contraction & dilatation, strongly elastick, & in a word, much like air in all respects, but far more subtile. 2. I suppose this aether pervades all gross bodies, but yet so as to stand rarer in their pores then in free spaces, & so much ye rarer as their pores are less ... 3. I suppose ye rarer aether within bodies & ye denser without them, not to be terminated in a mathematical superficies, but to grow gradually into one another.

I have presented principles of philosophy that are not, however, philosophical but strictly mathematical-that is, those on which the study of philosophy can be based. These principles are the laws and conditions of motions and of forces, which especially relate to philosophy.

All knowledge and understanding of the Universe was no more than playing with stones and shells on the seashore of the vast imponderable ocean of truth.

Therefore, the causes assigned to natural effects of the same kind must be, so far as possible, the same.