We need to look at what is real past thinking mind. For some there is nothing outside of thinking mind. For others there is life itself. Thinking mind is a small thing. Life is pervasive. When we look at life, without thinking how it should be, then we become aware of it's characteristics. This direct appreciation of the characteristics of life/reality/mind is what counts as realization in Mahamudra.
The Blessed One said:
"What is the All? Simply the eye & forms, ear & sounds, nose & aromas, tongue & flavors, body & tactile sensations, intellect & ideas. This, monks, is called the All. Anyone who would say, 'Repudiating this All, I will describe another,' if questioned on what exactly might be the grounds for his statement, would be unable to explain, and furthermore, would be put to grief. Why? Because it lies beyond range." Sabba Sutta.