Science doesn't care about authority or consensus. Although consensus
usually is based on the best available scientific evidence, science is based on what nature tells us. Yes, there is a lot that we don't know about human development, but we have mapped every singe step of development in simpler organisms like the roundworm,
C. elegans. Human development has quite a bit of research around it as well. We know enough about development in other animals and humans to say that what Bruce Lipton touts in his books and talks is bunk. What about his statements remain valid, to you?
The basic premise that our bodies (and health) can by influenced by our thoughts, beliefs, and emotions. That, I believe is valid. I was never very good at biology or chemistry and the realm of genetics is a little over my head as far as understanding exactly how DNA and RNA along with proteins, etc. work to change cell structure and or bodily functions. You can "show me" that his science is flawed, yet I will hold onto the "belief" that it is possible to change our physiology by changing our emotional make up and through the power of prayer, conscious thought (or meditation). The placebo effect to me, is the greatest example of how important our "beliefs" are to our physical health.