ignorance or ego

wherever I go there are many living examples seen about barriers to learning .

which is the most difficult barrier?

Ignorance of the value of knolwedge and its application or ego?

In our country we have many thongs in abundant supply

these are 

1. ignorance(അജ്ഞത )
2. ego(അഹങ്കാരം )
3. selfishness(സ്വാര്‍ത്ഥത )
4. avarice(അത്യാഗ്രഹം )
5. sloth (അലസത )

  which is the biggest barrier?

and we are all comfortable that we know everything