Chapter II. On Conscience

(St. Thomas, I, q. 79, a. 13; I-II, q. 19, a. 5; In II Sent., dist. 24, q. 2, a. 4; De Veritate, q. 17, a. 1; Quodlibet 8, q. 6, aa. 13 and 15; St. Alphonsus, Theologia moralis, bk. I, nn. 20-89, ed. Gaude; Homo Apostolicus, tr. 1).¹

¹ Cf. Waffelaert, De dubio solvendo in re morali dissertatio; Gaude, De morali systemate S. Alphonsi Mariae de Ligorio historico-theologica dissertatio; Ter Haar, De systemate morali antiquorum probabilistarum dissertatio historico-critica; Ven. Innocentii PP. XI de Probabilismo Decreti Historia et Vindiciae (1924); Le Bachelet, La question Ligorienne; De Caigny, De gemino probabilismo licito; De genuino morali systemate S. Alphonsi; Mandonnet, Le Decret d'Innocent XI contre le probabilisme; Lehmkuhl, Probabilismus vindicatus; Jansen, Geschichte und Kritik im Dienste der Minus-probabilis; Wouters, De Minusprobabilismo; Pagani, De regulis ad certam nobis conscientiam praestandam brevis tractatio; Arendt, Aequiprobabilismus ab ultimo fundamento discussus; Bucceroni, Commentarii... Commentarius secundus de Conscientia et de Probabilismo; Frins, De actibus humanis, pars III, De formanda conscientia; Valensise, Super systema Theol. Mor. hodie in scholis evulgatum brevis disquisitio; Mondino, Studio storico-critico sui sistema morale di S. Alfonso; Beaudouin-Gardeil, Tractatus de conscientia; Noble, La conscience morale; Wurth, Die psychologischen Grundlagen der Gewissensbildung; Fernus, Zur Vorgeschichte der Moralsysteme von Vitoria bis Medina; Chollet, "Conscience," in Dict. de theol. Cath. III, cols. 1156-1174; Van Oosterhout, Psychologie van het geweten; Rombouts, Geweten en gewetensvorming; Sweens, Theologia moralis fundamentalis; Delerue, Le systeme moral de St. Alphonse de Liguori.

After we have spoken of the remote rule of morality, or law, we must discuss the proximate rule of morals, or conscience. Namely, in order that law here and now, or in second act, oblige, it is required that it become known to the individual and be applied by him to a particular act. But it is applied to a particular act through conscience, which, as St. Thomas teaches, "adds to knowledge the application of knowledge to a particular act" (De verit., q. 17, a. 2, ad 2). And this is conscience properly so called, which accordingly imports a judgment concerning the morality of a particular act.

But conscience is also taken in a less proper sense for a habit or custom of judging about the morality of acts in this or that way; and thus strict, lax, and scrupulous conscience are distinguished. For the sake of practice we shall also undertake discussion of conscience considered in this way. Hence there is a twofold paragraph: the former concerning conscience properly so called, the latter concerning conscience improperly so called.