  In 1931, Banach proved that, far from being exceptional objects, the
Weierstrass functions form a residual set in the space $\mathcal{C}[0,1]$ of
continuous functions. Later on, in 1966, V. I. Gurariy showed that, except for
zero, there is an infinite-dimensional linear subspace of Weierstrass
functions. This was the first example of \textit{lineability}. Over the last
decade, this topic has attracted the continuous attention of the mathematical
community, with a steady stream of papers being published, many of them in
highly ranked mathematical journals. Several lineability criteria are known and
applied to specific topological vector spaces. To paraphrase L.
Bernal-Gonz\'alez and M. O. Cabrera in [J. Funct. Anal. \textbf{266} (2014),
3997-4025], ``sometimes, such criteria furnish unified proofs of a number of
scattered results in the related literature''. In this article, we provide a
general lineability criterion in the context of complements of vector spaces.
