It is well known that the Buddha teaches us to abandon all attachment ('upādāna'). However, attachment doesn't only refer to material things, and to feelings and emotions, it also includes views and opinions ('Diṭṭhi').
Normally, when we hold a certain view and are strongly convinced of it, we will actually not call it a 'view' or an 'opinion'. Instead, we call it 'truth', 'fact', 'the science'. We cling to that view, and identify with it, our view becomes an important part of our sense of identity ('sakkāya-diṭṭhi'). Once the view has become an integral part of our delusion of self, we will hold on to it and defend it, quite independent from the actual content of that view. Never mind if that view is factually true or not, never mind if it's harmful for me or others, we will defend it as if our life depends on it - because in a sense it does, as our delusion of self now depends on that view. Abandoning that view would feel as if we lost our identity.
Therefore, arguing about the content of opposing views is often a futile exercise. Both sides will not accept even the most convincing arguments, as they are ultimately fighting over their own identity, over their sense of self. They will rather become irrational and defy logic, than 'losing' what they take to be a part of their self.
The Buddha takes a different approach. In fact, the Buddha's analysis of cinging to views is one of the unique characteristics of his teaching, not to be found in that form in any other religion or philosophy. He shows that any view, doctrine, philosophy, religion, dogma, is a conditioned phenomenon. Views arise due to certain causes and conditioning factors, and they change and pass away when the conditions change. No view, dogma or doctrine can ever be 'right' in an absolute sense, as they are all 'sankhata', they are all constructed, made, thought out, changeable, unsure, uncertain. They depend on language, notions, concepts, words, ideas, perceptions, which are all conditioned phenomena themselves.
The Buddha guides us to look not only at the content of our views. He encourages us to investigate where our views comes from, what are the causes and conditions that formed our views. For instance, imagine you had been adopted at a young age and grown up in a devout muslim family in Oman. Would you have the same views as you have now? Or imagine you spend 10 years retreat in a monastery without any internet or access to mass media. Then you come out and live in 'normal' society again. Would you still have the same views as the 'normal' people around you, or would you rather find it difficult to relate to their opinons at all? Could you even relate to your own views 10 years back? Or, using a less extreme and perhaps more realistic scenario, even reading just one really good book can sometimes change our views dramatically.
So, which of these views is the 'real' or 'true' one?
Which of them is really you, your identity, your self?
Obviously, none, as they are all changing, constructed and put together by conditions.
The Great Disciple Anāthapiṇḍika, declared foremost in generosity among male lay disciples by the Buddha, expresses this insight perspiciously in Anguttara Nikāya/Numerical Discourses, Book of Tens, #93:
"Now this view has come into being and is conditioned, intentionally thought out, dependently originated.
But whatever has come into being and is conditioned, intentionally thought out, dependently originated, is impermanent.
Whatever is impermanent is suffering.
It is just suffering that one is attached to and holds on to."
Thus we contemplate the arising and passing of views, their conditioned nature. Once we can see all views and doctrines as a 'sankhāra', something that's put together, intentionally thought out, arising and passing away due to causes, impermanent, we can no longer maintain any naive belief in the 'absolute truth' of any view. We recognize that holding on to any view as our identity, as our self, is a futile and ultimately disappointing mistake.
And we can finally let go.
Of course, 'letting go' doesn't mean that we now don't have any views anymore. But it means that we're no longer identified with any view, we don't regard any view as our self. As we now practise to abandon 'sakkāya-diṭṭhi' ('entity-view'), we no longer need any views to prop up the illusion of identity.
However, we still understand the difference of wholesome and unwholesome views. We actually deliberately develop 'right view', meaning a view which is helpful and beneficial for developing the Noble Eightfold Path, weakening defilements, and leading us to the end of suffering. Understanding the conditioned origin of views, we also understand that views are not only based on conditions, but that they are also conditions themselves, producing certain results, generating effects. For example, if I hold the view that generosity and kindness will bring the karmic result of a fortunate rebirth and wealth and happiness, a likely result of that view is that I will make an effort to actually practise generosity and kindness.
We deliberately develop right view, we consciously strengthen our faith in right view, but not in order to cling to it, not to hold on to it as an identity or 'self'. We simply use right view to achieve our objective, which is abandoning all attachments and realizing Nibbāna. Just like an engineer creates a specific tool, and then uses that tool to build the thing he requires. Or, to use a simile of the Buddha, we use right view like a raft to support us in crossing over to the further shore, not to proudly carry it around on our head.
“Bhikkhus, I shall show you how the Dhamma is similar to a raft, being for the purpose of crossing over, not for the purpose of grasping."
"Kullūpamaṃ vo, bhikkhave, dhammaṃ desessāmi nittharaṇatthāya no gahaṇatthāya."
(Majjhima Nikāya/Middle Length Discourses, #22 'Simile of the Snake)
Again, Anāthapiṇḍika really nails it, when he explains the right view of a Noble Disciple; a view that is not clung to, but instead used as a tool to abandon all clinging; a view that's not so much a view but rather a meditation theme for letting go of all views, and all conditioned phenomena whatsoever:
"Whatever has come into being and is conditioned, intentionally thought out, dependently originated, is impermanent.
Whatever is impermanent is suffering.
Whatever is suffering:
'That's not mine; that's not me; that's not my self.'
That is my view"
(Anguttara Nikāya/Numerical Discourses, Book of Tens, #93)