“The distinguishing of the strata, or layers, in the embryonic membrane was a turning-point in the study of the history of evolution, and placed later researches in their proper light. A division of the (disc-shaped) embryo into an animal and a plastic part first takes place. In the lower part (the plastic or vegetative layer) are a serous and a vascular layer, each of peculiar organization. In the upper part also (the animal or serous germ-layer) two layers are clearly distinguishable, a flesh-layer and a skin-layer. (1828)” FirstsTwoLightAnimalStudyEvolutionResearchSkinsOrganizationFleshDivisionPeculiarLayersPlasticGermsTurning PointsEmbryosDiscsMembranes Author:Karl Ernst von Baer
“Know thyself! This is the source of all wisdom, said the great thinkers of the past, and the sentence was written in golden letters on the temple of the gods. To know himself, Linnæus declared to be the essential indisputable distinction of man above all other creatures. I know, indeed, in study nothing more worthy of free and thoughtful man than the study of himself. For if we look for the purpose of our existence, we cannot possibly find it outside ourselves. We are here for our own sake.” IfsKnowsMenLooksSaidPastSciencePurposeExistenceStudyWrittenSourceCreaturesEssentialsLettersSakeWorthySentencesGoldenThoughtfulDistinctionTemplesThinkerThyselfKnow ThyselfGreat Thinkers Author:Karl Ernst von Baer
