These words refer to a flexible or complaisant attitude that shuns applying rules too strictly or that is more generous than standards of discipline or conduct might allow if interpreted literally. Lenient indicates a generous or indifferent lowering of standards, especially in the context of discipline meted out by a superior or authority. It is the most neutral of these words in its implications, although it can easily take on a mild tone either of approval or disapproval: a prep school that was more lenient than most towards minor infractions of the rules; arguing that rigid regimentation militates against learning, while an atmosphere of lenient approval assists it; He lacked a sense of responsibility because of his lenient upbringing.

Merciful and lax are distinct from all these other words in adding to the general meaning an extreme emotional tone. They contrast sharply with each other, as well, merciful regarding the lenient attitude from a strongly favourable viewpoint, lax from nearly as strong a negative viewpoint. Merciful , furthermore, suggests compassion, lax laziness, indifference or slipshod incompetence.

• He begged the headmaster to be merciful ; The book’s worth was invalidated by its lax standards of accuracy; When the spirit and letter of the law appear to be in conflict, a judge is merciful, not lax , in upholding the spirit.

Indulgent is seldom neutral. It can carry a mild positive charge. Suggesting generosity, in a context pertaining to affectionate relationships; sometimes in such a context, however, and in most other uses, it is more strongly negative, suggesting undiscriminating or irresponsible complaisance: a jolly, indulgent uncle; too indulgent of her children’s every caprice or tantrum; a magazine that is indulgent of the unexamined prejudices and meretricious tastes of its readers. Tolerant is far less emotionally charged, approaching neutral description in most uses. In addition to indicating a flexible attitude towards rules of standards, it can suggest approval for an open-minded reluctance to make hasty judgements or disapproval for condescending rather than equal treatment: he informed his students that he could be tolerant of those who fell asleep in his class provided they didn’t snore; tolerant of the attitudes and beliefs of others; tolerant of but not enthusiastic about the new teenage fads.

Permissive is a much more formal word than the others, referring descriptively to an educational approach that allows the child’s interest and capacities to determine content and rate of progress: the permissive theories of progressive education. The word, less specifically, may refer to an extremely lenient way of child-rearing.

• The children of permissive parents often give their own children an authoritarian upbringing, and vice versa.

Partisans of a permissive approach, in either context, might use the term in neutral description, but critics of this approach may well use the word as a pejorative label: permissive theories that resulted, at best, in well-adjusted ignoramuses. Outside the contexts of education and psychology, the word is widely used as a synonym for tolerant , but goes beyond the latter in suggesting not only open-minded detachment but a passive acceptance of involvement as well: the question of how permissive girls should be when they start going out with boys.