What is the meaning of delusion? and how to get rid of it?

The robbers greed on others' stuffs because they ignore(delusion) of knowing and seeing the truth whether where will they get by robbing (karma).

They can't see their past lives, so they don't know the truth whether what is the resultant of greed on others' stuffs.

That's what the Buddha did on the enlightening night, 3 vijja.

AN 1.49-52 says:

Luminous, monks, is the mind. And it is defiled by incoming defilements.

Luminous, monks, is the mind. And it is freed from incoming defilements.

The suttas describe the defilement "greed" or "lust" as the mind "coloured" or "painted", similar to say a woman who, under the power of lust, paints her face with make-up in order to make herself more attractive or seductive. Thus SN 46.55 says about "lust":

Imagine, Brahman, a bowl of water mixed with lac, turmeric, dark green or crimson dye. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was. In the same way, Brahman, when a man dwells with his heart possessed and overwhelmed by sense-desires... then he cannot know or see, as it really is, what is to his own profit, to the profit of others, to the profit of both. Then even sacred words he has long studied are not clear to him, not to mention those he has not studied.

In contrast, the defilement of "delusion" is described as "darkness" or "spiritual/mental blindness. Thus about "doubt", which is a form of "delusion", SN 46.55 says:

Imagine a bowl of water, agitated, stirred up muddied, put in a dark place. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was. In the same way, Brahman, when a man dwells with his heart possessed and overwhelmed by doubt-and-wavering... then he cannot know or see, as it really is, what is to his own profit, to the profit of others, to the profit of both. Then even sacred words he has long studied are not clear to him, not to mention those he has studied.

Therefore, delusion is a primal or underlying "darkness" or "blindness", which can be the foundation for "greed" or "hatred". "Greed" is a desire to get something; where has "hatred" is a desire to destroy something. Regardless, both "greed" & "hatred" have their foundation in "delusion", which is "mental/spiritual blindness/darkness".

In a very general sense, delusion is wrong view. Wrong view includes:

1. Being blind to the reality killing, stealing, sexual misconduct, lying, intoxicants, gambling, etc, are harmful to oneself & harmful to others.

2. Being blind to the reality craving & attachment lead to suffering.

3. Being blind to the reality conditioned things are impermanent & lack lasting happiness and being blind to the reality all things lack self and are not self.

4. Being blind to the actually of the origination, the disappearance, the gratification, the danger and the escape in regard to feeling (MN 148).

For example, in SN 42.3, a man had wrong view, as follows:

Then Yodhajiva the headman went to the Blessed One and, on arrival, having bowed down to him, sat to one side. As he was sitting there he said to the Blessed One: "Lord, I have heard that it has been passed down by the ancient teaching lineage of warriors that 'When a warrior strives & exerts himself in battle, if others then strike him down & slay him while he is striving & exerting himself in battle, then with the breakup of the body, after death, he is reborn in the company of devas [gods; angels] slain in battle.' What does the Blessed One have to say about that?

Or in MN 87 a man had wrong view, as follows:

The Blessed One said to him “That’s the way it is, householder. That’s the way it is—for sorrow, lamentation, pain, distress & despair are born from one who is dear, come springing from one who is dear.”

“But lord, who would ever think that sorrow, lamentation, pain, distress & despair are born from one who is dear, come springing from one who is dear? Happiness & joy are born from one who is dear, come springing from one who is dear.” So the householder, not delighting in the Blessed One’s words, rejecting the Blessed One’s words, got up from his seat and left.

Or MN 115 says about right view & wrong view:

‘It’s impossible for a person accomplished in view to take any condition as permanent. That is not possible. But it’s possible for an ordinary person to take some condition as permanent. That is possible.’ They understand: ‘It’s impossible for a person accomplished in view to take any condition as pleasant. But it’s possible for an ordinary person to take some condition as pleasant.’ They understand: ‘It’s impossible for a person accomplished in view to take anything as self. But it’s possible for an ordinary person to take something as self.’

There are at least two ways to get rid of delusion & wrong view:

1. Wise analytical reasoning/thinking/reflection, as explained in MN 19

2. Direct insight via meditation, i.e., developing the Noble Eightfold Path.

Any time a model of reality in your head is out of sync with reality - that's delusion.

You know something, you think you know, and you are convinced that what you know is how it is - but it is not. You are delusional.

Perhaps someone lied to you and you believed them. Or perhaps you misunderstood. Or overgeneralized and applied knowledge that was correct about one piece - to another piece and there it's wrong. Or perhaps you just don't want to see reality as it is for emotional reasons - because admitting it would be too painful. Or even if you ate a wrong mushroom. Whatever is the reason.

Lust, passion, greed - are secondary. You are convinced something will make you happy or whole and you crave it. Delusion is the root cause.

Now, what is non-delusion? It's not simply being in-sync with reality, because we can never be 100% accurate about everything. Models are models, they are simplified and incomplete by their very nature. Although certainly being reasonably well educated and informed goes a long way. But the key requirement for non-delusion is not assuming you know more than you do!

Non-delusion requires humbleness and open mind. When we admit that our knowledge is tentative and partial, we can keep updating it as we go along. Being like this we are never out of sync, never deluded.

Not being out of sync, we are not subject to conflict. Not being subject to conflict, we do not suffer. That is how non-delusion is Peace.

Delusion, gives birth to lust, passion and greed. When the Delusion is conquered, there is nothing to attaching with lust, passion or greed. No one to feel those feelings.

The biggest Delusion is the delusion of self. The process of interpreting the external stimuli with past memories allow us to both identify and evaluate our interpretation of the world. This world we make ourselves is unique and personal to each person. The primary reason for building the whole world is to ascertain that I exist:

• I can see the world. The World exists, Because I can see the word I exist.
• I can hear the world. The World exists, Because I can hear the word I exist.
• I can taste the world. The World exists, Because I can taste the word I exist.
• I can feel the world. The World exists, Because I can feel the word I exist.
• I spoke to the world. The World exists, Because I can spoke to the word I exist.
• I remember seeing this house, talking to this person, tasting this taste, feeling this thing, hearing this sound yesterday. I remember the past, therefore I existed in the past.
• I will say, do, see, hear, feel tomorrow as well, therefore I will exist in the future.

Studying the Dukkha Sacca from Four Noble Truths, we can clearly see that the (Please read this answer which explains Dukkha Sacca in 4 noble truths. For brevity, I will not repeat it.) this person we think as I is the biggest Delusion that we create. When we are caught in this Delusion we spend all our energy in continuously ascertaining that I exist. Not only that based on that Delusion, we continue to evaluate our interpretation of the world, and start interacting with it with lust, greed, passion, anger, grief, etc. We think the person (I) is interacting with the world. But in reality, the world and the process of interpretation (that we call I) are one and the same. So, the lust, passion, greed, whatever the emotion, its only you. Its not the outside. Its only an interpretation of;

• photons that the eye collected
• sound wave the ear collected
• touch that the skin collected
• chemical that the tongue collected
• chemical that the nose collected
• an idea that the mind collected

The delusion is that we make a whole world based on the above, not only that we make a self who perceives it. This is the biggest Delusion.

Studying the four noble truths paves clear path out of this Delusion.

Please refer:

• MN 1 Mūlapariyāyasutta
• MN 44 Cūḷavedallasutta
• MN 2 Sabbāsavasutta
• DN 9 Poṭṭhapādasutta
• MN 8 Sallekhasutta
• Saccavibhaṅga

What is the meaning of delusion?

• it is one's wrong views, lack of insight, wrong conviction, the opposite of clear comprehension

and how it is different from lust , passion or greed ?

• delusion is that in dependence on which the others exist.

Suppose a person is new to the game and is fascinated by it.

This fascination can be seen to be due to the novelty of the game and this passion will remain until the ignorance about the game theory & mechanics is removed by clear comprehension.

When knowledge arises and the game is comprehended then the player will know the right strategy and will no longer become upset or greedy playing the game as he did when was ignorant.

Following a strategy requires also concentration and this is how the faculties are tied up. One can furthermore exert oneself following a strategy based on faith, without having attained knowledge & vision for oneself, expecting to attain it as a matter of course.

And finally , how to get rid of delusion ?

• By learning the teacher's instruction and doing as told.

When asked about greed, hatred and delusion, Venerable Ānanda replied:

AN3.71:4.2: A deluded person, overcome by delusion, intends to hurt themselves, hurt others, and hurt both. They experience mental pain and sadness.
AN3.71:4.3: When delusion has been given up, they don’t intend to hurt themselves, hurt others, and hurt both. They don’t experience mental pain and sadness.
AN3.71:4.4: A deluded person does bad things by way of body, speech, and mind.
AN3.71:4.5: When delusion has been given up, they don’t do bad things by way of body, speech, and mind.
AN3.71:4.6: A deluded person doesn’t truly understand what’s for their own good, the good of another, or the good of both.
AN3.71:4.7: When delusion has been given up, they truly understand what’s for their own good, the good of another, or the good of both.
AN3.71:4.8: Delusion is a destroyer of sight, vision, and knowledge; it blocks wisdom, it’s on the side of anguish, and it doesn’t lead to extinguishment.
AN3.71:4.9: This is the drawback we’ve seen in greed, hate, and delusion, and this is why we advocate giving them up.”

To get rid of delusion, there is a path:

AN3.71:5.4: “It is simply this noble eightfold path, that is:
AN3.71:5.5: right view, right thought, right speech, right action, right livelihood, right effort, right mindfulness, and right immersion.
AN3.71:5.6: This is the path, this is the practice for giving up that greed, hate, and delusion.”

Although AN3.71 defines delusion in terms of its effects on ourselves and others, a list of delusions might help. Notice that identity view is #1 in the list of delusions (Sakkāyadiṭṭhi...moho):

AN6.90:1.3: Identity view, doubt, misapprehension of precepts and observances, and forms of greed, hate, and delusion that lead to rebirth in places of loss.

Delusion is unskillful because it leads us to value and chase impermanent things again and again. When asked about their identity, people will often respond with a list of impermanent things (e.g., my house, my job, my car, my computer, my partner, etc.). That identification leads to inevitable suffering, which is why identity view is a delusion. The hook of delusion is desire, a desire for impermanent things. Desiring impermanent things is delusion for those seeking an end to suffering.

SN42.11:4.4: “Then was it because you saw or heard of her that you had
SN42.11:4: desire or love or fondness for her?”
SN42.11:4.6: “Yes, sir.”
SN42.11:5.1: “What do you think, chief?
SN42.11:5.2: If Ciravāsi’s mother was executed, imprisoned, fined, or condemned, would it cause you sorrow, lamentation, pain, sadness, and distress?”
SN42.11:5.3: “How could it not, sir?”
SN42.11:5.4: “This too is a way to understand:
SN42.11:5.5: ‘All the suffering that arises is rooted and sourced in desire.
SN42.11:5.6: For desire is the root of suffering.’”

This last point is a difficult teaching. In particular, the monks who heard this same teaching in MN1 were not happy:

MN1:172-194.30: That is what the Buddha said.
MN1:172-194.31: But the mendicants were not happy with what the Buddha said.