Lifestyle—generally a living entity born by father and mother he is considered a śūdra. Just like in ordinary life we send our children to school or college's for knowledge. So janmanā jāyate śūdraḥ, anyone who is born is ignorant—foolish, otherwise why is he sent to school or college? He is supposed to be foolish. So education means according to the qualities there must be examination by the teachers who is fit for becoming a brāhmin, who is fit for becoming a kṣatriya, and who is fit for becoming a vaiśya like that.
Of course śūdras were not given any education or they were incapable of receiving education. Especially the brāhmins and kṣatriyas were educated to guide the social welfare. That is the Vedic system and therefore Kṛṣṇa says, cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ. Guṇa and karma—not by birth, Kṛṣṇa says by quality and by work. One must be qualified brāhmin by the symptoms, truthfulness, controlling the mind, controlling the senses very simple simplicity of life. Ārjavam, jñānam, vijñānam—full of knowledge, vijñānam—practical application is life.
Āstikyam—theistic view, in this way one becomes brāhmin. Similarly kṣatriyas qualifications are described, vaiśyas qualifications are also described. The brāhmins qualifications nine, kṣatriyas qualifications seven, reducing. Vaiśyas qualifications three, kṛṣi-go-rakṣya-vāṇijyaṁ, kṛṣi—means agriculture, go-rakṣya—cow protection that is vaiśyas business and the kṣatriyas business is to give protection to the citizens, human beings. Similarly the vaiśyas business is to give protection to the cows. Cow is very important animal in the society.