Sei Lá (A Vida Tem Sempre Razão) is a Brazilian Portuguese song with music by Toquinho and lyrics by Vinícius de Moraes. Its styles are given as MPB, samba and bossa nova, and it is catalogued under the Latin genre. The original recording was made by Toquinho and Vinícius de Moraes as a duo in 1971 and released on the album Toquinho e Vinicius (Discos RGE), where it appears as track B1 under the title Sei Lá... A Vida Tem Sempre Razão.
The song has lyrics. Later versions include recordings by Os Caretas (1972), Chico Buarque, Miúcha and Antonio Carlos Jobim (1977), Mart'nália (2005) and Toquinho with Paulo Ricardo (2011). Stefano Bollani recorded an instrumental version in 2015. These later versions show how far the song has travelled beyond its original 1971 release.
