This is ultimately derived from Kant, who taught that our senses are unreliable. This led later philosophers to dispense with external reality and start with sense perception.
This makes a certain kind of sense. If you do not believe that your senses observe reality as it really is, then why not dispense with external reality and start with sense perceptions? This is essentially what Kant followers, including Bohr, did.
Let’s now look at Bohr’s acceptance of the particle-wave duality that comes up when identifying the nature of light and hence his rejection of the Law of Identity.
Rejection of the Law of Identity
“The situation which we meet here is characterized by the fact that we are apparently forced to choose between two mutually contradictory conceptions of the propagation of light. One, the idea of light waves, the other, the corpuscular view of the of the theory of light quanta, each conception expressing fundamental aspects of our experience. As we shall see in the following, this apparent dilemma marks a particular limitation of our forms of perception which is bound up with the quantum of action.” 
We have already mentioned this particular quote when discussing Bohr’s acceptance of contradictions and the alleged failure of our forms of perceptions and his rejection of reality and objective facts.
But now, let’s take a look at the particular aspect of this quote that points to his belief on the nature of light.
Bohr accepts the contradiction that exists between the wave theory of light and the corpuscular or particle theory of light. He accepts this contradiction, taking it as an indication of the limitation of our faculty of perception and in doing so rejects the law of identity rather than reject the contradiction of particle-wave duality and accept the law of identity.
Is particle-wave duality a reasonable concept and could it be possible that this is a valid part of quantum mechanics? No, even a casual grasp of the Law of Identity makes it clear that particle-wave duality is an impossibility.
Everything that exists has a specific nature. Or, to put it simply: To be, is to be something. Everything that exists is subject to this basic principle, be it a mountain or the smallest subatomic particle.
To exist is to have a specific, non-contradictory nature. If something is a particle, it is not also a non-particle.
The concept of “particle” and “wave” are mutually exclusive. A particle is a kind of physical entity. It is one form physical entities exist in. It is simply one way of saying “that thing that exists, it is this kind of thing”.
But the concept of a wave is not the same kind of concept. A wave is not a form of physical existence. It is an abstraction which identifies relationships. It identifies relationships between the properties of entities, which might be physical entities or other abstractions.
For instance, “water waves” do not have a physical existence. The “wave” does not have physical existence.
What physically exists is water. What we refer to when we point to a “wave” of water is water arranged in a certain kind of spatial relationship. That is a certain kind of relationship between the position of water molecules.
[Editorial: Does this mean the water wave does not exist? Well, it means that the water and its relationships exist. But the wave is simply an abstraction].
It is no different when you talk about “light waves”, “electron waves” or any other kind of wave phenomena observed on the quantum scale.
Waves are not things. When someone says an electron is a wave, they are saying that an electron is an abstraction identifying relationships.
But, if an electron is a physical object, then it cannot also be an abstraction. Therefore, no physical entities can be both a particle, ie a physical object and a wave, ie an abstraction.
Whatever physical object you observe, it is not a wave. Whenever you observe a wave, you are observing relationships. Whether they be relationships of one or more physical entities or the changing properties of the same physical entities. If light is a wave, then there is something waving.
So, no there is no justification for alleging particle-wave duality. No experiment has ever actually proven this to be the case.
What then to make of the double slit experiments and the like which are purported to prove that electrons are both waves and particles? And other such experiments?
They do not show that electrons or anything else are both particles and waves. They show that when you perform such experiments, under certain conditions you observe particle behavior and under other conditions you observe waves.
But, that does not prove that electrons are both waves and particles. You cannot explain the behavior of electrons by appealing to non-physical so-called “explanations” which violate the Law of Identity.
What then does the double slit experiment demonstrate the nature of light? That remains to be seen. But, you cannot explain the observations of such experiments by appealing to non-physical explanations which attempts to establish a contradiction and to treat a physical entity as an abstraction.
And yet Bohr did just that, under the influence of philosophical tenets he already held. As we have mentioned already, his concept of “complementarity” was one of his most irrational and revealing philosophical notion, which embraces contradictions.
It is no wonder that this kind of philosophy ultimately led to the acceptance of the dual nature of light. The Law of Identity had already been rejected with the notion of “complementarity” and it is not a big leap from that to embracing the dual nature of light.
This is quite an example of how a philosophical idea such as complementarity has influenced and infected quantum mechanics. Let us now dive into a couple of quotes that shed light on his rejection of causality.