When we observe the processes of physical nature, we see that there is a clear transmission of basic traits of existence from one generation to the next with a coherent and repeatable result. The oak tree creates a seed which in turn creates a new oak tree. We see beings of one species giving birth to beings of the same species. There is also an obvious hereditary pattern at a finer level of detail, which is detailed by scientists in the science of genetics. Specific physical traits are clearly capable of being passed on from one generation to the next. It is not as simple as direct transmission as the process actually is built to create variation and diversity, through mingling of genetic characteristics of the parents in the offspring, and through the process of recessive traits being passed along through this mingling process.
While there is also a certain amount of mutation in the genetic process, this is still within the genus/species and does not create new beings from old forms.
What is not covered effectively by these facts are the higher mental and spiritual capabilities which clearly cannot be explained by a purely physical genetic process. If all these capacities were strictly limited to physical genetic transmission, we would see a strict class heredity of capabilities. We would however be unable to account for some of the dramatic “anomalies” that occur all too frequently, and which show a mental and spiritual capacity not in evidence in the parental stock.
Sri Aurobindo addresses these questions: “We are called upon to admit that the human seed for instance, which does not contain a developed human consciousness, yet carries with it the powers of such a consciousness so that they reproduce themselves automatically in the thinking and organised mentality of the offspring. This, even if we have to accept it, is an inexplicable paradox unless we suppose either that there is something more behind, a psychical power behind the veil of material process, or else that mind is only a process of life and life only a process of matter. Therefore finally we have to suppose the physical theory capable of explaining by purely material causes and a material constitution the mystery of the emergence of life in matter and the equal mystery of the emergence of mind in life. It is here that difficulties begin to crowd in which convict it, so far at least, of a hopeless inadequacy, and the nature of that inadequacy, its crux, its stumbling-point leave room for just that something behind, something psychical, a hidden soul process and for a more complex and less materialistic account of the truth of evolution.”