Reality

Like real pain and real illness or disability, the specifications depend upon the "perceiving" individual. Reality is perception but perception is not necessarily reality. We use our senses and we process the input using our perceptions, beliefs and the culture in which we live to form our reality. Reality is based upon both internal and external environments also influenced by culture, beliefs and individual perceptions as accepted by the group and the individual per the group.

We depend on sight, touch, hearing, smell and taste to feed us our external realities. How they are filtered is through all the above influences. 

You can not trust the perceptions derived from you feelings for they tend to distort and disrupt reality, i.e. for example the effects of chemical dumps in the mind and body from anger and fear. Your perceptions are often controlled by what others say or do, what is fashionable at the time for the group according to its cultures and beliefs, whether it is a part of the group or individuals ethnic makeup, and what power relationships are involved between you and others and the group dynamics. 

Then the question and difficulty of discovering, seeking, reality must be addressed especially when it comes to conflicts - both social and physical, etc. To perceive reality requires an open mind and careful attention to things that are yielding from adequate and unbiased data. It takes knowing the perceptions of reality differ from one person to another regardless. 

Another bit of reasoning to train the mind for a mind-state that reaches a level of "mushin." In martial arts reality is that set of immutable principles that cross over to all combatives and self-defense. The universal fundamental principles of yin-yang as in a microcosmic discipline of life called martial arts. Immutable and indisputable. 

It is therefore up to you as the martial artist to define and train for reality.