The experimental approach has been at the center of my thoughts since my baccalaureate of "experimental sciences". Trained in neurosciences, I very quickly chose the field of ethology, thinking I would escape certain experimental approaches and offer myself research more respectful of animal life. Today, I have to note that this option did not necessarily lead to what I had imagined. I have been both the witness and the actor of practices that deserve attention. This path, punctuated by an evolution of the conceptions of our relations with living beings, leads me to question the ethics, sometimes contradictory, of action and knowledge.