我愛你 x4 the secret to happiness is love is an album by Taiwanese singer/actress/model Vivian Hsu, released September 28, 2003 on the Avex label. The Chinese script in the title read Wǒ Ài Nǐ, which means, "I Love You". There were three versions of this album produced: a limited edition with artbook, a preorder edition with artbook and bonus single CD, and a regular edition without the artbook, but with a VCD with some music videos on it.
This album contains Vivian's first rap song, Mianju, which was later featured in the compilation album Ji Le 175 (Template:極樂 175). Also featured is Jueding Ai Ni (決定愛你; Juédìng Ài Nǐ), the theme song to the TV series Love Storm, in which Vivian starred.
Catalog number (limited edition): AVTCD-90034
Catalog number (regular edition): AVTCD-95723