The living cell during Darwin’s day were thought of as “simple” basic structures of membranes and nucleic “blobs”.
So such thing as “simple life”.
Today we know this was a massive blunder. Scientists continue to learn more with each passing day largely thanks to the power of the electronic microscope and genetics. Each discovery brings yet another devastating blow to the ignorant ideas of the 1850’s when a living cell was referred as “simple”. In fact, we now recognize that living cells are complex molecular machines of unimaginable complexity and genius.