As a material entity, then, the soul could reasonably begin at the zygote stage--perhaps the consequence of rearrangements in egg cytoplasm that occur during fertilization--and progress through a continuum of development until it reaches "maturity" in the adult human being.
(the soul; could reasonably begin; T:at the zygote stage; T:As a material entity; T:then) (rearrangements in egg cytoplasm; occur; T:during fertilization) (the soul; progress; T:until it reaches "maturity" in the adult human being; T:then) (it; reaches; maturity; T:in the adult human being)
the soul rearrangements in egg cytoplasm the soul it
could reasonably begin occur progress reaches
T:at the zygote stage T:As a material entity T:then
T:during fertilization
T:until it reaches "maturity" in the adult human being T:then
maturity T:in the adult human being