Four valid factors 四量（具量原典、具量闡釋、具量上師、具量覺受）

Four valid factors (Tib. tséma shyi; Wyl. tshad ma bzhi) of Lamdré:

• valid scripture (lung tséma),
• valid commentaries (tenchö tséma),
• valid teacher (lama tséma), and
• valid experience (nyam nyong tséma).

They arose in this order, but in a student’s experience it goes the other way. First a student develops some valid experience, then appreciates the importance and value of a teacher. Once one has respect for the teacher one has more respect for the commentaries he or she teaches, and then for the original scriptures taught by the Buddha.