In the Theravāda tradition, the precepts are usually taken "each separately" (), to indicate that if one precept should be broken, the other precepts are still intact. In very solemn occasions, or for very pious devotees, the precepts may be taken as a group rather than each separately. This does not mean, however, that only some of the precepts can be undertaken; they are always committed to as a complete set. In East Asian Buddhism, however, the vow of taking the precepts is considered a solemn matter, and it is not uncommon for lay people to undertake only the precepts that they are confident they can keep. The act of taking a vow to keep the precepts is what makes it karmically effective: Spiro found that someone who did not violate the precepts, but did not have any intention to keep them either, was not believed to accrue any religious merit. On the other hand, when people took a vow to keep the precepts, and then broke them afterwards, the negative karma was considered larger than in the case no vow was taken to keep the precepts.