ɪt mˈiːnz ðæt tɹˈuːθtˈɛlɪŋ ɪz ɐ wˈiːklidˈɑːmɪnənt stɹˈæɾədʒi, ˈaɪ.ˈiː. juː fˈɛɹ bˈɛst ɔːɹ æt lˈiːst nˌɑːt wˈɜːs baɪ bˌiːɪŋ tɹˈuːθfəl, ɹᵻɡˈɑːɹdləs ʌv wʌt ðɪ ˈʌðɚz dˈuː.
It means that truth-telling is a weakly-dominant strategy, i.e. you fare best or at least not worse by being truthful, regardless of what the others do.