“But mindfulness, bhikkhus, is needed at all times.”In many suttas one who has mindfulness is described thus:
~ Saṃyutta-Nikāya, Bojjhaṅgasaṃyutta, Sutta 53
“...a bhikkhu is mindful, one who possess the highest mindfulness and discrimination, who remembers and recalls what was done and said long ago.”This description of mindfulness in the Suttas brings out its aspect of memory. In the commentary also mindfulness is explained in relation to memory:
~ e.g. Dīgha-Nikāya, Saṅgīti Sutta
“It is mindfulness (sati) because by means of it they remember (saranti); or it itself remembers; or it is just mere-remembering.”However, mindfulness is categorized in Abhidhamma as a beautiful-mental-factor, which means that while it is always found associated with wholesome consciousness (kusala-citta), it can never be found in association with unwholesome consciousness (akusala-citta). This means that mindfulness is absent when a person performs an unwholesome action like killing, stealing, etc.
~ Dhammasaṅgaṇi-Aṭṭhakathā
But if mindfulness is related to memory how could it be absent when a person performs an unwholesome action? Does this mean that a person who is killing or stealing has no recollection of things he had said or done? This would be absurd since memory is such a fundamental function of our mind that it should be common to all kinds of consciousness regardless of whether they are wholesome or unwholesome. A mental factor (cetasika) that is to perform the function of memory should by right fall into the category of those that are common to all consciousness, i.e. the universals (sabbacittasādhāraṇa). Assuming that the Suttas is correct then either mindfulness had been wrongly classified in the Abhidhamma, or there is something more to memory than just mindfulness.