Mutualism is an 18th-century economic theory that was developed into anarchist theory by Pierre-Joseph Proudhon.
mjˈuːtʃuːəlˌɪzəm ɪz ɐn ˈeɪtiːnθsˈɛntʃɚɹi ˌiːkənˈɑːmɪk θˈiəɹi ðæt wʌz dɪvˈɛləpt ˌɪntʊ ˈænɑːɹkˌɪst θˈiəɹi baɪ pɪˈɛɹdʒˈoʊsəf pɹˈaʊdhɑːn.