Jainism says a blade of grass has a soul as real as yours

Mahavira taught that every living thing -- not just animals, but plants, insects, even particles of earth, water, fire, and air -- holds a jiva, a soul equally capable of suffering. Because violence harms a real soul wherever it falls, Jain ethics builds ahimsa into daily life: filtering water, sweeping the path ahead of your feet, eating to kill as little as possible. Karma here isn't metaphor -- it's subtle matter that clings to the soul whenever you act with violence.

— Umasvati, Tattvartha Sutra — Chapter 2, on the nature of jiva (soul), c. 2nd-5th century CE