One of the three gunas, or qualities of nature. The quality of darkness, foulness, ignorance, obscurity, heaviness or inertia. The “lowest” of the three qualities. From the Mahabarata: "Complete delusion, ignorance, illiberality, indecision in respect of action, sleep, haughtiness, fear, cupidity, grief, censure of good acts, loss of memory, unripeness of judgment, absence of faith, violation of all rules of conduct, want of discrimination, blindness, vileness of behaviour, boastful assertions of performance when there has been no performance, presumption of knowledge in ignorance, unfriendliness (or hostility), evilness of disposition, absence of faith, stupid reasoning, crookedness, incapacity for association, sinful action, senselessness, stolidity, lassitude, absence of self-control, degradation, - all these qualities are known as belonging to Darkness (Tamas). Whatever other states of mind connected with delusion exist in the world, all appertain to Darkness. Frequent ill-speaking of other people, censuring the deities and the Brahmanas (priests), illiberality, vanity, delusion, wrath, unforgiveness, hostility towards all creatures, are regarded as the characteristics of Darkness. Whatever undertakings exist that are unmeritorious (in consequence of their being vain or useless), what gifts there are that are unmeritorious (in consequence of the unworthiness of the donee, the unseasonableness of the time, the impropriety of the object, etc.), vain eating, - these also appertain to Darknesss (Tamas). Indulgence in calumny, unforgiveness, animosity, vanity, and absence of faith are also said to be characteristics of Darkness. Whatever men there are in this world who are characterised by these and other faults of a similar kind, and who break through the restraints provided by the scriptures, are all regarded as belonging to the quality of Darkness."