Any cause that negatively affects mortality, positively affects mortality, negatively affects survivorship, and positively affects survivorship is tetraeffective (i.e., having four kinds of effects). However, until now, tetraeffective causes of mortality and survivorship have been undescribed, unidentified, unnamed, unrecognized, unclear, misconceived, unspecified, and unexplained. Here I describe, identify, name, recognize, elucidate, conceptualize, specify, and explain tetraeffective causes of mortality and survivorship. I show that every tetraeffective cause of mortality and survivorship combines corresponding at least one mortacause and at least one vitacause; mortacause refers here to a cause that positively affects mortality and negatively affects survivorship, and vitacause refers to a cause that positively affects survivorship and negatively affects mortality. I present strong rationales that suggest that every cause of mortality and survivorship is tetraeffective, and I present references to considerable previous evidence that I interpret to be suggestive evidence of tetraeffective causes of mortality and survivorship. Moreover, rigorous and thorough multivariable analyses of mortality and survivorship of humans and medflies provide here direct evidence of tetraeffective causes of mortality and survivorship, revealing best-fitting specifications dY/d(Xp) = a + bXp such that sign(a) = -sign(bXp), where: Y indicates mortality or survivorship; X indicates age, lifespan, contemporary aggregate size, lifespan aggregate size, or historical time; a indicates an X-specific mortacause or vitacause; bXp indicates the corresponding opposite X-specific mortacause or vitacause; and coefficients a, b, and p denote respective X-specific and entity-specific constants. Thus description, identification, naming, recognition, elucidation, conception, specification, explanation, and demonstration of tetraeffective causes of mortality and survivorship usher a new paradigm of causes of mortality and survivorship and enable and promote further scientific research and practical applications.