In this quote, Seneca seems to be suggesting that life is a continuous battle or fight that we should take part in. He may be referring to the truth that we are constantly confronted with challenges and obstacles that we need to get rid of in order to make it through and thrive. This could consist of everything from personal battles like health problem, financial issues, and relationship concerns, to wider societal obstacles like discrimination, violence, and political unrest. By describing it as warfare, Seneca is possibly highlighting the fact that the struggle we face is often extreme and needs a lot of strength, resilience, and decision to get rid of. Ultimately, he may be motivating us to view life as a battle worth battling and to approach it with a warrior's frame of mind.
"Life is life - whether in a cat, or dog or man. There is no difference there between a cat or a man. The idea of difference is a human conception for man's own advantage"