CLUB - An assembly of good fellows, meeting under certain conditions. Samuel Johnson
The wise man does not expose himself needlessly to danger, since there are few things for which he cares sufficiently; but he is willing, in great crises, to give even his life - knowing that under certain conditions it is not worthwhile to live. Aristotle
For under certain conditions the chemical atoms emit light waves of a specific length or oscillation frequency - their familiar characteristic spectra - and these can come in the form of electromagnetic waves only from accelerated electric quanta. Johannes Stark
If co-operation is a duty, I hold that non-co-operation also under certain conditions is equally a duty. Mahatma Gandhi