Full Idea
The whole of philosophy is like a tree. The roots are metaphysics, the trunk is physics, and the branches emerging from the trunk are all the other sciences.
Gist of Idea
Metaphysics is the roots of the tree of science
Source
René Descartes (Preface to 'Principles of Philosophy' [1647]), quoted by A.W. Moore - The Evolution of Modern Metaphysics 01.2
Book Reference
Moore,A.W.: 'The Evolution of Modern Metaphysics' [CUP 2013], p.28
A Reaction
If Descartes had not believed this he would not have bothered with metaphysics, and philosophy might have been dead by 1650.