Previously, most glosses and research on the Yogācāra Bodhisattva Precepts had taken the vantage of the Six Paramitas or the Four Samgrahas. In this paper I use statistics and analysis to examine the psychology and ethical standpoints of the Yogācāra Bodhisattva Precepts. First, I divide the contents of the Precepts concerning the mental elements into three categories, the Polluted Breach, the Non-polluted Breach, and the Non-breach, in accordance with the definitions of the Yogācāra School. This school's classes of vexations are also used to clarify these three categories. Next, I have made classifications and statistics for the mental elements conditions of the Polluted Breach, the Non-polluted Breach, and the Non-breach, so that the Bodhisattva practitioner may recognize each psychological state. In this way, when such moods occur, the practitioner is aware that they may cause certain behaviors and breaches of the precepts. The Yogācāra Bodhisattva Precepts are similar to other Bodhisattva precepts in that they emphasize preventing psychological conditions relating to the four main precepts governing greed, stinginess, anger, and insolent to others. As to the 43 secondary precepts, statistics show that moods motivated by hate (āghāta), springing from Polluted Breach mental elements, are listed the most times (19). If the closely related moods of anger and enmity are included, the count goes up to 25, accounting for 58% of the total. From this we may see that 'hate' is the main objective of the Yogācāra Boddhisttva Precepts. In the category of Non-polluted breaches, laziness (ālasya-kausīdya) appears most often, accounting for some 21% of the total with 19 appearances. This shows that diligence is a key mental element of the Yogācāra Bodhisattva Precepts. The conditions relating to Non-breaches most often appearing is taming and subduing, at 15 times about 35% of the total. Motivated by good intent, this type of behavior brings living creatures harmony with good dharma, so it is classified as a Non-breach. Analyses of the Ninth, the some main crimes which are in special condition, shows that the standards by which good and bad behavior are measured in the Precepts are the motives and results. If the result is altruistic, and the motive is sympathy, this behavior may be a sort of convenience. Such an act does not count as bad behavior or language, but rather earns great merit. In other words, the Precepts do not designate any particular action as being absolutely good or bad (such as maintaining that killing or robbing and so on are absolutely bad regardless of whether or not the motive is good and the results are altruistic.)