146 EMBRYOLOGY IN THE SEVENTEENTH [pt. 11 



seek the diversity of the causes of parts out of the diversity of the 

 matter from whence they should be framed. So Physicians affirm, 

 that the different parts of the body are fashioned and nourished by 

 the different materials of blood or seed ; namely the softer parts, as 

 the flesh, out of a thinner matter, and the more earthy parts as the 

 bones, out of grosser and harder. But this error now too much 

 received, we have confuted in another place. Nor are they lesse 

 deceived who make all things out of Atomes, as Democritus, or out 

 of the elements, as Empedocles. As if (forsooth) Generation were 

 nothing in the world, but a meer separation, or Collection, or Order 

 of things. I do not indeed deny that to the Production of one thing 

 out of another, these forementioned things are requisite, but Genera- 

 tion her self is a thing quite distinct from them all. (I finde Aristotle 

 in this opinion) and I my self intend to clear it anon, that out of 

 the same White of the Egge (which all men confesse to be a similar 

 body, and without diversity of parts) all and every the parts of the 

 chicken whether they be Bones, Clawes, Feathers, Flesh, or what 

 ever else, are procreated and fed. Besides, they that argue thus 

 assigning only a material cause, deducing the causes of Natural 

 things from an involuntary or casual concurrence of the Elements, 

 or from the several disposition or contriving of Atomes ; they doe 

 not reach that which is chiefly concerned in the operations of nature, 

 and in the Generation and Nutrition of animals, namely the Divine 

 Agent, and God of Nature, whose operations are guided with the 

 highest Artifice, Providence, and Wisdome, and doe all tend to some 

 certaine end, and are all produced, for some certaine good. But these 

 men derogate from the Honour of the Divine Architect, who hath 

 made the Shell of the Egge with as much skill for the egge's defence 

 as any other particle, disposing the whole out of the same matter 

 and by one and the same formative faculty." But although these are 

 Harvey's theories, it is significant that in his preface he says, "Every 

 inquisition is to be derived from its causes, and chiefly from the 

 material and efficient", thus expressly excluding formal and final 

 considerations. Certainly, as far as his practical work went, he was 

 unaffected by them, and in the case of the egg-shell, for example, 

 Harvey was not the man to say, "it is present for the protection of 

 the embryo", and then to do or say nothing more. Such an explana- 

 tion, though he might gladly accept it, was no bar to further explora- 

 tion both by way of experiment and observation. 



