The first philosophical approach to entomology deals with insects as small animals. Due to the physical differences linked with the difference of scale, small animals seem to live in another world. The second approach deals with nomenclature and classification. It shows the progressive making of the concept of insect. In this process, groups like the crustaceans or the spiders were split off from the insects. The third approach deals with the interpretation of insect societies. – Insects can offer to philosophy a set of thought experiments, which have not been fully exploited.