Whatever creates or increases happiness or some part of happiness, we ought to do; whatever destroys or hampers happiness, or gives rise to its opposite, we ought not to do.

[τὰ μὲν γὰρ παρασκευάζοντα ταύτην ἢ τῶν μορίων τι, ἢ μεῖζον ἀντ᾽ ἐλάττονος ποιοῦντα, δεῖ πράττειν, τὰ δὲ φθείροντα ἢ ἐμποδίζοντα ἢ τὰ ἐναντία ποιοῦντα μὴ πράττειν.]

Aristotle (384-322 BC) Greek philosopher

Rhetoric [Ῥητορική; Ars Rhetorica], Book 1, ch. 5, sec. 2 (1.5.2) / 1360b.11 (350 BC) [tr. Roberts (1924)]
    (Source)

(Source (Greek)). Alternate translations:

For it behoves us to perform those acts which procure [happiness], or any one of its constituent parts, or which, when it is little, render it greater; but not to perform those which destroy, or obstruct it, or produce its contraries.
[Source (1847)]

We needs do the things which procure [happiness] or any of its constituents, or which render it greater from having been less, and refrain from doing the things which destroy or impede it, or produce its opposites.
[tr. Buckley (1850)]

Since we ought to do those things which tend to create [Happiness] or any one of its parts, or to increase that part; but we ought not do those things which corrupt, or hinder it, or produce its opposite.
[tr. Jebb (1873)]

For one should do the things which procure happiness or one of its parts, or increase instead of diminishing it, and avoid doing those things which destroy or hinder it or bring about what is contrary to it.
[tr. Freese (1926)]

After all, we are bound to act in a way that creates the conditions for happiness or one of its constituents, or at any rate increases rather than diminishes it, and to avoid doing things that destroy or hinder it or have outcomes that oppose it.
[tr. Waterfield (2018)]