Human beings are creatures of the mind. Every child is born with a clean heart and developing intellect. Depending on the child's needs and the way they are met, or not met, the child responds emotionally and intellectually to pain or pleasure; with contentment or greed, love or distrust, anger or violence, hatred or compassion. Self consciousness at the earlier stage may develop into self confidence or vain pride. The last of these is described by Guru Nanak as "haumai" which means hau-mai or "me-me". And this haumai is a malignant disease, present everywhere:

O Nanak, malignant is the disease of ego.
Wherever I see, I see the pain of same malady
Lord himself absolves through the Word.
nwnk haumY rog bury [
jh dyKW qh eykw bydn Awpy bKsY sbid Dury ]
(GGS, p. 1153)

It is this haumai which leads to waywardness -- greed, and disregard for other people's rights.

It is this haumai which, according to Guru Nanak, stands between man and God. He says:

"When there was haumai in me, there was not Thou.
When there is Thou, there will be no I-ness."
haumY krI qW qU nwhI qU hovih hau nwhI [
(GGS, p. 1092)

An egocentric can not love God,
for His heart is putrefied with self conceit.
mnmuK qy AB Bgiq n hovis haumY mY pcih idvwny [
(GGS, p. 1345)

A body that is not attuned to His Name
Is infested with pride and strife.
ijq qin nwmu n BwveI iqqu qin haumY vwdu [
(GGS, p. 61)

When the Word abides in mind,
Egotism is eliminated from within.
gur kw sbdu min visAw haumY ivchu Koie [
(GGS, p. 61)

O Naive, forget the egoist perception
Still your ego and meditate on the Lord within.
BoilAw haumY suriq ivswir [
haumY mwir bIcwir mn gux ivic guxu lY swir [
(GGS, p. 1127)

He who stills his haumai obtains bliss through the Word.
hamY myit sbid suK hoie [
(GGS, p. 1040)

To shun vain pride and self-conceit one has to understand the Will of the One Lord and presence of the same spirit within all beings. It helps one to understand equality and regard for other people's rights and liberties.

If one were to understand the Divine Will
No one will say 'me me'
nwnk hukmY jy buJY q haumY kih n koie [
(GGS, p. 1)

If one were to realize the same Lord within us all
No one will say 'me me'.
Srb jIA mih eyko jwxY qw haumY kih n koie [
(GGS, p. 432)

He alone is said to be emancipated in life
Within whom ego is stilled
jIvn mukqu so AwKIAY ijs ivchu haumY jwie [
(GGS, p. 1010)

If one were to discard the self-conceit, endowed with self confidence one could deal with others without fear or enmity; one would be compassionate and thereby also achieve contentment and bliss.

With me me attitude one can not reach the Truth
One can attain the highest stage {bliss], if ego departs
hau hau krq nhI scu pweIAY
haumY jwie prm pd pweIAY [
(GGS, p. 226)

Guru Nanak's view is clear that:

1. It is a person's egoism that stands between him and the Primal Being.
2. This self-conceit leads a person astray and promotes selfishness, greed, anger, lust, and other unhealthy states of mind and wayward behaviour.
3. If one were to let the Lord abide in one's heart that would help the person get rid of his self conceit, or vice versa, if the person were to shun egoism, one would welcome the Lord within, leading to discard of wayward behaviour, acceptance of equality of all human beings, thereby achieving contentment and bliss and even salvation in life.