Guru can be one or many.Datta traya had 32 gurus' to elevate himself as Mahaguru.One who learns from all GOOD can only be a guru esp when one keeps on learning.A Professor is a life long student -of his facultyor branch of study.Let good fresh thoughts come to us from all side...Timely thoughtful and thorough action is guided by a specialist Guru/s at each turn of your path..the sad buddhi to find a proper person or a creation which can truly guides us the best is a god given gift of snaskaras.Those who are eager to learn, humble to accept counter view with grace and respect,put thought before biases,value the true advice even when bitter...are likely to find proper teachers..and only these ones can later become a true teacher for those coming later in this path of life..Teacher and student relationship is like mother earth each leads to the other..in different forms..your mind should be traines to identify a true one in each..both are same later..the teacher and the taught..Salute to all great teachers who have left behind better teachers than them...as students..who continue to lead this path of human evolution..of mind and matter.. pic;1..Duryodhanas 'never learn from 'Krishnas'..bad students..''Krishna shishthayi''krishna teaching kauravas the tragedy of war and goodness of sharing and compromise..but fails,,, pic 2;the teacher and the taught,both are great..even ganesha god of learning learns!